A semiconductor device and a manufacturing method thereof

Abstract

The application provides a semiconductor device and a manufacturing method thereof, which comprises a substrate, a first temperature-variable barrier layer located on the substrate, a first temperature-variable recrystallization layer located on the first temperature-variable barrier layer, and a gallium oxide epitaxial layer located on the first temperature-variable recrystallization layer. By forming the temperature-variable barrier layer and the temperature-variable recrystallization layer between the substrate and the gallium oxide epitaxial layer, enough nucleation centers are provided for epitaxial growth of the gallium oxide epitaxial layer, the crystal quality of the gallium oxide epitaxial layer is improved, the defect density of the gallium oxide epitaxial layer is reduced, and a foundation is laid for subsequent manufacturing of power electronic devices.

Description

Technical Field

[0001] This application relates to the field of semiconductor technology, and more specifically to a semiconductor device and a method for manufacturing the same. Background Technology

[0002] Wide-bandgap radio frequency (RF) and power electronics will define many critical transportation and communication systems, including radar. This success is based on the higher conversion efficiency achievable with wide-bandgap materials; currently, silicon carbide (SiC) and gallium nitride (GaN) meet this requirement, but real-world needs extend even beyond these performance metrics. Nevertheless, producing large-scale, cost-effective, and high-quality GaN and SiC substrates remains a major challenge in the development of power electronics based on these wide-bandgap materials.

[0003] Low on-resistance, high breakdown voltage, and low leakage current in the off-state are key parameters required for low-loss, high-power, and high-frequency switching. To achieve these parameters, the selected semiconductor material must possess high breakdown field strength, wide bandgap, and high electron mobility. Among these, the novel ultra-wide bandgap semiconductor material, monoclinic gallium oxide (β-Ga₂O₃), meets these requirements.

[0004] To realize the full application potential of β-Ga2O3, several fundamental challenges need to be addressed. One of these challenges is the high-quality epitaxial growth of the material. Metal-Organic Chemical Vapor Deposition (MOCVD) has become an ideal choice for β-Ga2O3 epitaxial growth due to its advantages such as fast growth rate, low cost per wafer, good uniformity, and mass production capability. Although the preparation of β-Ga2O3 via MOCVD epitaxial growth technology has the aforementioned advantages, obtaining β-Ga2O3 epitaxial films with ideal low defect density still presents some difficulties.

[0005] Therefore, improvements are needed to at least partially address the aforementioned problems. Summary of the Invention

[0006] The summary section introduces a series of simplified concepts, which will be further explained in detail in the detailed description section. This summary section is not intended to limit the key and essential technical features of the claimed technical solution, nor is it intended to determine the scope of protection of the claimed technical solution.

[0007] To address the existing problems, this application provides a semiconductor device, comprising: a substrate; a first temperature-changing barrier layer located on the substrate; a first temperature-changing recrystallization layer located on the first temperature-changing barrier layer; and a gallium oxide epitaxial layer located on the first temperature-changing recrystallization layer.

[0008] For example, it further includes: a second temperature-changing barrier layer located on the first temperature-changing recrystallization layer; a second temperature-changing recrystallization layer located on the second temperature-changing barrier layer; a third temperature-changing barrier layer located on the second temperature-changing recrystallization layer; and a third temperature-changing recrystallization layer located on the third temperature-changing barrier layer.

[0009] Another aspect of this application provides a method for manufacturing a semiconductor device, comprising: providing a substrate, forming a first temperature-variable barrier layer on the substrate; forming a first temperature-variable recrystallization layer on the first temperature-variable barrier layer; and forming a gallium oxide epitaxial layer on the first temperature-variable recrystallization layer.

[0010] For example, the growth pressure for forming the first temperature-varying barrier layer is 20 mbar-100 mbar, the molar flow ratio of oxygen to gallium is 300-700, the carrier gas is high-purity nitrogen or high-purity argon, and the growth temperature and growth time include: the growth temperature in the first stage is 500℃-550℃, and the growth time is 1 min-5 min; the growth temperature in the second stage is 550℃-600℃, and the growth time is 3 min-8 min; the growth temperature in the third stage is 600℃-650℃, and the growth time is 5 min-10 min.

[0011] For example, the growth pressure for forming the first temperature-varying recrystallized layer is 50 mbar-300 mbar, the molar flow ratio of oxygen to gallium is 200-600, the carrier gas is high-purity nitrogen or high-purity argon, and the growth temperature and growth time include: the growth temperature in the first stage is 600℃-650℃, and the growth time is 1 min-5 min; the growth temperature in the second stage is 650℃-700℃, and the growth time is 1 min-5 min; the growth temperature in the third stage is 700℃-750℃, and the growth time is 5 min-10 min.

[0012] For example, it further includes: forming a second temperature-changing barrier layer on the first temperature-changing recrystallization layer; forming a second temperature-changing recrystallization layer on the second temperature-changing barrier layer; forming a third temperature-changing barrier layer on the second temperature-changing recrystallization layer; and forming a third temperature-changing recrystallization layer on the third temperature-changing barrier layer.

[0013] For example, the growth pressure for forming the second temperature-variable barrier layer is 20 mbar-100 mbar, the molar flow ratio of oxygen to gallium is 300-700, the carrier gas is high-purity nitrogen or high-purity argon, and the growth temperature and growth time include: the growth temperature in the first stage is 700℃-750℃, and the growth time is 3 min-8 min; the growth temperature in the second stage is 750℃-800℃, and the growth time is 5 min-10 min; and the growth temperature in the third stage is 800℃-850℃, and the growth time is 10 min-15 min.

[0014] For example, the growth pressure for forming the second temperature-dependent recrystallization layer is 50 mbar-300 mbar, the molar flow ratio of oxygen to gallium is 200-600, the carrier gas is high-purity nitrogen or high-purity argon, and the growth temperature and growth time include: the growth temperature in the first stage is 800℃-850℃, and the growth time is 1 min-5 min; the growth temperature in the second stage is 850℃-900℃, and the growth time is 1 min-5 min; the growth temperature in the third stage is 900℃-1000℃, and the growth time is 5 min-10 min.

[0015] For example, the growth pressure for forming the third temperature-variable barrier layer is 20 mbar-100 mbar, the molar flow ratio of oxygen to gallium is 300-700, the carrier gas is high-purity nitrogen or high-purity argon, and the growth temperature and growth time include: the growth temperature in the first stage is 850℃-900℃, and the growth time is 5 min-10 min; the growth temperature in the second stage is 900℃-950℃, and the growth time is 10 min-15 min; the growth temperature in the third stage is 950℃-1000℃, and the growth time is 15 min-20 min.

[0016] For example, the growth pressure for forming the third temperature-variable recrystallization layer is 50 mbar-300 mbar, the molar flow ratio of oxygen to gallium is 200-600, the carrier gas is high-purity nitrogen or high-purity argon, and the growth temperature and growth time include: the growth temperature in the first stage is 950℃-1000℃, and the growth time is 1 min-5 min; the growth temperature in the second stage is 1000℃-1050℃, and the growth time is 1 min-5 min; the growth temperature in the third stage is 1050℃-1100℃, and the growth time is 5 min-10 min.

[0017] The semiconductor device and its manufacturing method provided in this application can provide sufficient nucleation centers for the epitaxial growth of gallium oxide epitaxial layer by forming a temperature-variable barrier layer and a temperature-variable recrystallization layer between the substrate and the gallium oxide epitaxial layer, thereby improving the crystal quality of the gallium oxide epitaxial layer and reducing the defect density of the gallium oxide epitaxial layer, laying the foundation for the subsequent fabrication of power electronic devices. Attached Figure Description

[0018] The above and other objects, features, and advantages of this application will become more apparent from the more detailed description of the embodiments of this application in conjunction with the accompanying drawings. The drawings are provided to further illustrate the embodiments of this application and form part of the specification. They are used together with the embodiments of this application to explain this application and do not constitute a limitation thereof. In the drawings, the same reference numerals generally represent the same components or steps.

[0019] In the attached image:

[0020] Figure 1 A schematic cross-sectional view of a semiconductor device according to a specific embodiment of this application is shown;

[0021] Figure 2 A cross-sectional schematic diagram of a semiconductor device according to another specific embodiment of this application is shown;

[0022] Figure 3 A flowchart illustrating a method for manufacturing a semiconductor device according to a specific embodiment of this application is shown. Detailed Implementation

[0023] In the following description, numerous specific details are set forth in order to provide a more thorough understanding of this application. However, it will be apparent to those skilled in the art that the invention may be practiced without one or more of these details. In other instances, certain technical features well-known in the art have not been described in order to avoid obscuring the invention.

[0024] It should be understood that this application can be implemented in various forms and should not be construed as limited to the embodiments set forth herein. Rather, providing these embodiments will make the disclosure thorough and complete, and will fully convey the scope of the invention to those skilled in the art. In the drawings, for clarity, the dimensions and relative dimensions of layers and regions may be exaggerated. The same reference numerals denote the same elements throughout.

[0025] It should be understood that when an element or layer is referred to as "on," "adjacent to," "connected to," or "coupled to" other elements or layers, it may be directly on, adjacent to, connected to, or coupled to other elements or layers, or there may be intervening elements or layers. Conversely, when an element is referred to as "directly on," "directly adjacent to," "directly connected to," or "directly coupled to" other elements or layers, there are no intervening elements or layers. It should be understood that although the terms first, second, third, etc., may be used to describe various elements, components, areas, layers, and / or portions, these elements, components, areas, layers, and / or portions should not be limited by these terms. These terms are only used to distinguish one element, component, area, layer, or portion from another element, component, area, layer, or portion. Therefore, without departing from the teachings of this invention, the first element, component, area, layer, or portion discussed below may be referred to as the second element, component, area, layer, or portion.

[0026] Spatial relation terms such as “below,” “under,” “below,” “under,” “above,” “above,” etc., are used herein for convenience of description to describe the relationship between one element or feature shown in the figure and other elements or features. It should be understood that, in addition to the orientation shown in the figure, spatial relation terms are intended to also include different orientations of the device in use and operation. For example, if the device in the figure is flipped, then the element or feature described as “below” or “under” the other element or feature will be oriented “above” the other element or feature. Therefore, the exemplary terms “below” and “under” can include both upper and lower orientations. The device may be otherwise oriented (rotated 90 degrees or otherwise) and the spatial descriptive terms used herein will be interpreted accordingly.

[0027] The terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the invention. When used herein, the singular forms “a,” “an,” and “the” are also intended to include the plural forms unless the context clearly indicates otherwise. It should also be understood that the terms “comprising” and / or “including,” when used in this specification, identify the presence of the stated features, integers, steps, operations, elements, and / or components, but do not exclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and / or groups. When used herein, the term “and / or” includes any and all combinations of the associated listed items.

[0028] Unless otherwise defined, all terms used herein (including technical and scientific terms) shall have the same meaning as commonly understood by one of ordinary skill in the art. It will also be understood that terms as defined in commonly used dictionaries shall be construed as having a meaning consistent with their meaning in the relevant field and / or the context of this specification, and not as interpreted in an ideal or overly formal sense, unless expressly defined herein.

[0029] To fully understand this application, detailed steps and structures will be presented in the following description to illustrate the technical solutions proposed in this application. Preferred embodiments of this application are described in detail below; however, in addition to these detailed descriptions, this application may have other implementation methods.

[0030] In related technologies, a low-temperature Ga2O3 buffer layer is introduced between the substrate and the β-Ga2O3 epitaxial layer to obtain a β-Ga2O3 epitaxial film with ideal low defect density. However, the low-temperature Ga2O3 buffer layer is in a polycrystalline or amorphous state, which cannot provide sufficient nucleation centers for the subsequent epitaxial growth of the β-Ga2O3 epitaxial layer. Due to the low temperature of the buffer layer, elements (such as C) after the decomposition of the precursor may not have time to be desorbed and attached to the epitaxial structure, affecting the crystal quality of the epitaxial layer and hindering the fabrication of power electronic devices.

[0031] Therefore, in view of the aforementioned technical problems, this application proposes a semiconductor device, comprising:

[0032] Substrate;

[0033] The first temperature-varying barrier layer is located on the substrate;

[0034] The first temperature-variable recrystallization layer is located on the first temperature-variable barrier layer;

[0035] The gallium oxide epitaxial layer is located on the first temperature-variable recrystallization layer.

[0036] The semiconductor device provided in this application, by forming a temperature-controlled barrier layer and a temperature-controlled recrystallization layer between the substrate and the gallium oxide epitaxial layer, can provide sufficient nucleation centers for the epitaxial growth of the gallium oxide epitaxial layer, improve the crystal quality of the gallium oxide epitaxial layer, and reduce the defect density of the gallium oxide epitaxial layer, thus laying the foundation for the subsequent fabrication of power electronic devices.

[0037] Example 1

[0038] Below, for reference Figure 1 The semiconductor devices in the embodiments of this application will be described. Figure 1A cross-sectional schematic diagram of a semiconductor device according to a specific embodiment of this application is shown. The semiconductor device includes: a substrate 100; a first temperature-changing barrier layer 110 located on the substrate 100; a first temperature-changing recrystallization layer 120 located on the first temperature-changing barrier layer 110; and a gallium oxide epitaxial layer 130 located on the first temperature-changing recrystallization layer 120.

[0039] In one example, the material of substrate 100 includes, but is not limited to, at least one of the following: silicon (Si), gallium oxide (Ga2O3), germanium (Ge), silicon germanium (SiGe), silicon carbide (SiC), silicon germanium carbon (SiGeC), indium arsenide (InAs), gallium arsenide (GaAs), indium phosphide (InP), sapphire, or other III / V compound semiconductors; or silicon on dielectric (SOI), silicon on dielectric (SSOI), silicon germanium on dielectric (S-SiGeOI), silicon germanium on dielectric (SiGeOI), and germanium on dielectric (GeOI); or it may be a double-sided polished wafer (DSP), a ceramic substrate such as alumina, a quartz, or a glass substrate. In this embodiment, the material of substrate 100 may be a 2-inch, 4-inch, or 6-inch gallium oxide substrate, sapphire substrate, or silicon substrate, and there is no specific limitation thereto. Although several examples of materials that can form substrate 100 have been described herein, any material that can serve as substrate 100 falls within the spirit and scope of the invention.

[0040] In one example, a first temperature-varying barrier layer 110 is formed on the substrate 100. Exemplarily, the material of the first temperature-varying barrier layer 110 includes, but is not limited to, β-Ga2O3. During the growth of the first temperature-varying barrier layer 110, the temperature and time vary, and the growth temperature and time are divided into three stages: the first stage growth temperature is 500℃-550℃, and the growth time is 1 min-5 min; the second stage growth temperature is 550℃-600℃, and the growth time is 3 min-8 min; the third stage growth temperature is 600℃-650℃, and the growth time is 5 min-10 min. By growing the final first temperature-varying barrier layer 110 through these three stages of increasing temperature, the conventional buffer layer can mitigate the problem that elements (e.g., C) from the precursor decomposition at low temperatures may not have enough time to be resolved and grow in the epitaxial structure, thus affecting crystal quality. It can also limit the upward extension of defects.

[0041] In one example, a first temperature-varying recrystallization layer 120 is formed on the first temperature-varying barrier layer 110. Exemplarily, the material of the first temperature-varying recrystallization layer 120 includes, but is not limited to, crystalline gallium oxide (Ga2O3). During the growth of the first temperature-varying recrystallization layer 120, the temperature and time vary, and the growth temperature and time are divided into three stages: the first stage growth temperature is 600℃-650℃, and the growth time is 1 min-5 min; the second stage growth temperature is 650℃-700℃, and the growth time is 1 min-5 min; the third stage growth temperature is 700℃-750℃, and the growth time is 5 min-10 min. The first temperature-variable recrystallization layer 120 is formed by increasing the temperature in three stages. The first temperature-variable barrier layer 110 is combined with the first temperature-variable recrystallization layer 120. The temperature is increased in three stages from low to high. The subsequent epitaxial growth of gallium oxide epitaxial layer has better density and crystal quality, and reduces the defect density of gallium oxide epitaxial layer, laying the foundation for the subsequent fabrication of power electronic devices.

[0042] In one example, a gallium oxide epitaxial layer 130 is formed on the first temperature-controlled recrystallization layer 120. Exemplarily, the material of the gallium oxide epitaxial layer 130 includes, but is not limited to, N-type β-Ga2O3.

[0043] The semiconductor device provided in this application, by forming a temperature-controlled barrier layer and a temperature-controlled recrystallization layer between the substrate and the gallium oxide epitaxial layer, can provide sufficient nucleation centers for the epitaxial growth of the gallium oxide epitaxial layer, improve the crystal quality of the gallium oxide epitaxial layer, and reduce the defect density of the gallium oxide epitaxial layer, thus laying the foundation for the subsequent fabrication of power electronic devices.

[0044] Example 2

[0045] This application also provides a semiconductor device. The parts identical to those in Embodiment 1 described above will not be repeated here. Below, refer to... Figure 2 The semiconductor devices in the embodiments of this application will be described. Figure 2 A cross-sectional schematic diagram of a semiconductor device according to another specific embodiment of this application is shown. The semiconductor device includes: a substrate 100; a first temperature-changing barrier layer 110 located on the substrate 100; a first temperature-changing recrystallization layer 120 located on the first temperature-changing barrier layer 110; a second temperature-changing barrier layer 140 located on the first temperature-changing recrystallization layer 120; a second temperature-changing recrystallization layer 150 located on the second temperature-changing barrier layer 140; a third temperature-changing barrier layer 160 located on the second temperature-changing recrystallization layer 150; a third temperature-changing recrystallization layer 170 located on the third temperature-changing barrier layer 160; and a gallium oxide epitaxial layer 130 located on the third temperature-changing recrystallization layer 170.

[0046] In one example, a second temperature-variable barrier layer 140 is formed on the first temperature-variable recrystallization layer 120. Exemplarily, the material of the second temperature-variable barrier layer 140 includes, but is not limited to, β-Ga2O3. During the growth of the second temperature-variable barrier layer 140, the temperature and time vary in three stages: the first stage has a growth temperature of 700℃-750℃ and a growth time of 3-8 minutes; the second stage has a growth temperature of 750℃-800℃ and a growth time of 5-10 minutes; and the third stage has a growth temperature of 800℃-850℃ and a growth time of 10-15 minutes. By growing at progressively increasing temperatures in these three stages to form the final second temperature-variable barrier layer 140, the upward extension of defects can be further restricted.

[0047] In one example, a second temperature-variable barrier layer 140 is formed on the second temperature-variable barrier layer 140. Exemplarily, the material of the second temperature-variable recrystallization layer 150 includes, but is not limited to, crystalline gallium oxide (Ga2O3). During the growth of the second temperature-variable recrystallization layer 150, the temperature and time vary in three stages: the first stage has a growth temperature of 800℃-850℃ and a growth time of 1 min-5 min; the second stage has a growth temperature of 850℃-900℃ and a growth time of 1 min-5 min; and the third stage has a growth temperature of 900℃-1000℃ and a growth time of 5 min-10 min. By increasing the temperature in these three stages, the final second temperature-variable recrystallization layer 150 is formed. The combination of the second temperature-variable barrier layer 140 and the second temperature-variable recrystallization layer 150, with the temperature increasing in three stages from low to high, further improves the density and crystal quality of the subsequently grown gallium oxide epitaxial layer and further reduces the defect density of the gallium oxide epitaxial layer.

[0048] In one example, a third temperature-variable barrier layer 160 is formed on the second temperature-variable recrystallization layer 150. Exemplarily, the material of the third temperature-variable barrier layer 160 includes, but is not limited to, β-Ga₂O₃. During the growth of the third temperature-variable barrier layer 160, the temperature and time vary in three stages: the first stage has a growth temperature of 850℃-900℃ and a growth time of 5-10 minutes; the second stage has a growth temperature of 900℃-950℃ and a growth time of 10-15 minutes; and the third stage has a growth temperature of 950℃-1000℃ and a growth time of 15-20 minutes. By growing the final third temperature-variable barrier layer 160 through these three progressively increasing temperature stages, the upward extension of defects can be more effectively restricted, thereby improving the crystal quality of the gallium oxide epitaxial layer.

[0049] In one example, a third temperature-variable recrystallization layer 170 is formed on the third temperature-variable barrier layer 160. Exemplarily, the material of the third temperature-variable recrystallization layer 170 includes, but is not limited to, crystalline gallium oxide (Ga2O3). During the growth of the third temperature-variable recrystallization layer 170, the temperature and time vary, and the growth temperature and time are divided into three stages: the first stage growth temperature is 950℃-1000℃, and the growth time is 1 min-5 min; the second stage growth temperature is 1000℃-1050℃, and the growth time is 1 min-5 min; the third stage growth temperature is 1050℃-1100℃, and the growth time is 5 min-10 min. The final third temperature-variable recrystallization layer 170 is formed by increasing the temperature in three stages. The third temperature-variable barrier layer 160 is combined with the third temperature-variable recrystallization layer 170. The temperature increases in three stages from low to high. The subsequent epitaxial growth of gallium oxide epitaxial layer has good density and crystal quality, which allows defects to be redirected and annihilated at the growth interface to a greater extent. This can more efficiently reduce the defect density in the gallium oxide epitaxial process and lay the foundation for the subsequent fabrication of power electronic devices.

[0050] In one example, a gallium oxide epitaxial layer 130 is formed on the third temperature-controlled recrystallization layer 170. Exemplarily, the material of the gallium oxide epitaxial layer 130 includes, but is not limited to, N-type β-Ga₂O₃. By forming multiple temperature-controlled barrier layers and multiple temperature-controlled recrystallization layers between the substrate 100 and the gallium oxide epitaxial layer 130, most defects are redirected and annihilated at the growth interface, providing more nucleation centers for the epitaxial growth of the gallium oxide epitaxial layer 130, further improving the crystal quality of the gallium oxide epitaxial layer 130, and more efficiently reducing the defect density of the gallium oxide epitaxial layer 130, laying the foundation for the subsequent fabrication of power electronic devices.

[0051] Example 3

[0052] This application also provides a method for manufacturing a semiconductor device, such as... Figure 3 As shown, it mainly includes the following steps:

[0053] In step S1, a substrate is provided, and a first temperature-resistant barrier layer is formed on the substrate;

[0054] In step S2, a first temperature-variable recrystallization layer is formed on the first temperature-variable barrier layer;

[0055] In step S3, a gallium oxide epitaxial layer is formed on the first temperature-controlled recrystallization layer.

[0056] The semiconductor device manufacturing method of this application provides sufficient nucleation centers for the epitaxial growth of gallium oxide epitaxial layer by forming a temperature-controlled barrier layer and a temperature-controlled recrystallization layer between the substrate and the gallium oxide epitaxial layer, thereby improving the crystal quality of the gallium oxide epitaxial layer and reducing the defect density of the gallium oxide epitaxial layer, laying the foundation for the subsequent fabrication of power electronic devices.

[0057] Below, for reference Figure 1 and Figure 3 The method for manufacturing the semiconductor device of this application is described in detail, wherein, Figure 1 A schematic cross-sectional view of a semiconductor device according to a specific embodiment of this application is shown. Figure 3 A flowchart illustrating a method for manufacturing a semiconductor device according to a specific embodiment of this application is shown.

[0058] For example, the method for manufacturing the semiconductor device of this application includes the following steps:

[0059] First, step S1 is performed to provide a substrate and form a first temperature-changing barrier layer on the substrate.

[0060] In one example, the material of substrate 100 includes, but is not limited to, at least one of the following: silicon (Si), gallium oxide (Ga2O3), germanium (Ge), silicon germanium (SiGe), silicon carbide (SiC), silicon germanium carbon (SiGeC), indium arsenide (InAs), gallium arsenide (GaAs), indium phosphide (InP), sapphire, or other III / V compound semiconductors; or silicon on dielectric (SOI), silicon on dielectric (SSOI), silicon germanium on dielectric (S-SiGeOI), silicon germanium on dielectric (SiGeOI), and germanium on dielectric (GeOI); or it may be a double-sided polished wafer (DSP), a ceramic substrate such as alumina, a quartz, or a glass substrate. In this embodiment, the material of substrate 100 may be a 2-inch, 4-inch, or 6-inch gallium oxide substrate, sapphire substrate, or silicon substrate, and there is no specific limitation thereto. Although several examples of materials that can form substrate 100 have been described herein, any material that can serve as substrate 100 falls within the spirit and scope of the invention.

[0061] For example, the substrate 100 needs to be pretreated before forming the first temperature-changing barrier layer 110. Specifically, the substrate 100 is ultrasonically treated in deionized water for 10-30 minutes. The purpose of the pretreatment is to remove particulate contamination and residual dirt from substrate processing from the surface of the substrate 100, which is beneficial for the subsequent epitaxial growth of the thin film. After the treatment, the substrate 100 is dried in a dust-free environment.

[0062] In one example, such as Figure 1 As shown, a first temperature-varying barrier layer 110 is formed on the substrate 100. Exemplarily, the first temperature-varying barrier layer 110 includes, but is not limited to, β-Ga2O3. For example, a first gallium oxide bulk layer 110 is grown in a metal-organic chemical vapor deposition (MOCVD) reaction chamber. The growth pressure (i.e., the pressure of the MOCVD reaction chamber) is 20 mbar-100 mbar, the molar flow ratio of oxygen to gallium is 300-700, the carrier gas is high-purity nitrogen or high-purity argon, the oxygen source is high-purity oxygen or nitrous oxide, and the gallium source is trimethylgallium (TMGa) or triethylgallium (TEGa). The growth temperature (i.e., the temperature of the MOCVD reaction chamber) and growth time are varied and divided into three stages: the first stage growth temperature is 500℃-550℃, and the growth time is 1 min-5 min; the second stage growth temperature is 550℃-600℃, and the growth time is 3 min-8 min; the third stage growth temperature is 600℃-650℃, and the growth time is 5 min-10 min. By growing the first temperature-variable barrier layer 110 through three stages of progressively increasing temperature, the conventional buffer layer can mitigate the problem where elements (e.g., C) from precursor decomposition cannot be resolved in time and grow into the epitaxial structure due to the low temperature, thus affecting crystal quality. It can also limit the upward extension of defects. For example, as a combined embodiment, the growth temperatures and times for the three stages of growing the first temperature-variable barrier layer 110 are 525°C and 3 min, 575°C and 5 min, and 625°C and 7.5 min, respectively.

[0063] Next, step S2 is performed to form a first temperature-changing recrystallization layer on the first temperature-changing barrier layer.

[0064] In one example, such as Figure 1As shown, a first temperature-variable recrystallization layer 120 is formed on the first temperature-variable barrier layer 110. Exemplarily, the first temperature-variable recrystallization layer 120 includes, but is not limited to, crystalline gallium oxide (Ga2O3). Exemplarily, the first temperature-variable recrystallization layer 120 is grown in an MOCVD reaction chamber at a growth pressure of 50 mbar-300 mbar, an oxygen to gallium molar flow ratio of 200-600, a carrier gas of high-purity nitrogen or high-purity argon, an oxygen source of high-purity oxygen or nitrous oxide, and a gallium source of trimethylgallium (TMGa) or triethylgallium (TEGa). The growth temperature and growth time are varied, divided into three stages: the first stage growth temperature is 600℃-650℃, and the growth time is 1 min-5 min; the second stage growth temperature is 650℃-700℃, and the growth time is 1 min-5 min; the third stage growth temperature is 700℃-750℃, and the growth time is 5 min-10 min. For example, as a combined embodiment, during the growth of the first temperature-variable recrystallization layer 120, the growth temperatures and times for the three stages are 625°C and 3 min, 675°C and 5 min, and 725°C and 7.5 min, respectively. The final first temperature-variable recrystallization layer 120 is formed by increasing the temperature in three stages. The first temperature-variable barrier layer 110, combined with the first temperature-variable recrystallization layer 120, results in a three-stage temperature progression from low to high. This leads to better density and crystal quality in the subsequently grown β-Ga2O3 epitaxial layer, thereby reducing the defect density of the gallium oxide epitaxial layer and laying the foundation for the fabrication of subsequent power electronic devices.

[0065] Then, step S203 is performed to form a gallium oxide epitaxial layer on the first temperature-dependent recrystallization layer.

[0066] In one example, such as Figure 1 As shown, a gallium oxide epitaxial layer 130 is formed on the first temperature-controlled recrystallization layer 120. Exemplarily, the material of the gallium oxide epitaxial layer 130 includes, but is not limited to, N-type β-Ga₂O₃. Exemplarily, the gallium oxide epitaxial layer 130 is grown in an MOCVD reaction chamber at a growth pressure of 30 mbar-80 mbar, a growth temperature of 750°C-900°C, a carrier gas of high-purity nitrogen or high-purity argon, an oxygen source of high-purity oxygen or nitrous oxide, a gallium source of trimethylgallium (TMGa) or triethylgallium (TEGa), a silicon source of tetraethoxysilane (TEOS), and a silicon doping concentration of 1E¹⁵ atoms / cm². 3 -1E17atoms / cm 3 The VI / III ratio is 300-800. For example, the thickness of the gallium oxide epitaxial layer 130 can be 0.2um-3um, such as 0.2um, 0.5um, 0.8um, 1um, 1.3um, 1.6um, 2um, 2.5um or 3um.

[0067] It should be noted that after the gallium oxide epitaxial layer 130 is grown, the temperature of the MOCVD reaction chamber is reduced to below 150°C to end the entire epitaxial growth process.

[0068] Example 4

[0069] The preceding process steps in this embodiment are the same as those in Embodiment 3 above, and will not be described again here. Please refer to the following... Figure 2 The method for fabricating the semiconductor device according to the embodiments of this application is described in detail, wherein, Figure 2 A cross-sectional schematic diagram of a semiconductor device according to another specific embodiment of this application is shown.

[0070] In one example, such as Figure 2 As shown, a second temperature-changing barrier layer 140 is formed on the first temperature-changing recrystallization layer 120. Exemplarily, the second temperature-changing barrier layer 140 includes, but is not limited to, β-Ga2O3. For example, a second temperature-variable barrier layer 140 is grown in an MOCVD reaction chamber at a growth pressure of 20 mbar-100 mbar, an oxygen to gallium molar flow rate ratio of 300-700, a carrier gas of high-purity nitrogen or high-purity argon, an oxygen source of high-purity oxygen or nitrous oxide, and a gallium source of trimethylgallium (TMGa) or triethylgallium (TEGa). The growth temperature (i.e., the temperature of the MOCVD reaction chamber) and growth time are varied and divided into three stages: the first stage growth temperature is 700℃-750℃, and the growth time is 3 min-8 min; the second stage growth temperature is 750℃-800℃, and the growth time is 5 min-10 min; the third stage growth temperature is 800℃-850℃, and the growth time is 10 min-15 min. By growing at progressively increasing temperatures in three stages to form the final second temperature-variable barrier layer 140, the upward extension of defects can be further restricted. For example, as a combined embodiment, the growth temperature and growth time for the three stages of growing the second temperature-changing barrier layer 140 are 725°C and 5 min, 775°C and 7.5 min, and 825°C and 12.5 min, respectively.

[0071] In one example, such as Figure 2As shown, a second temperature-variable recrystallization layer 150 is formed on the second temperature-variable barrier layer 140. Exemplarily, the material of the second temperature-variable recrystallization layer 150 includes, but is not limited to, crystalline gallium oxide (Ga2O3). Exemplarily, the second temperature-variable recrystallization layer 150 is grown in an MOCVD reaction chamber at a growth pressure of 50 mbar-300 mbar, an oxygen to gallium molar flow ratio of 200-600, a carrier gas of high-purity nitrogen or high-purity argon, an oxygen source of high-purity oxygen or nitrous oxide, and a gallium source of trimethylgallium (TMGa) or triethylgallium (TEGa). The growth temperature and growth time are varied, divided into three stages: the first stage growth temperature is 800℃-850℃, and the growth time is 1 min-5 min; the second stage growth temperature is 850℃-900℃, and the growth time is 1 min-5 min; the third stage growth temperature is 900℃-1000℃, and the growth time is 5 min-10 min. For example, as a combined embodiment, during the growth of the second temperature-variable recrystallization layer 150, the growth temperatures and times for the three stages are 825°C and 3 min, 875°C and 5 min, and 950°C and 7.5 min, respectively. The final second temperature-variable recrystallization layer 150 is formed by increasing the temperature in three stages. The second temperature-variable barrier layer 140, combined with the second temperature-variable recrystallization layer 150, forms a temperature that increases in three stages from low to high. This further improves the density and crystal quality of the subsequently grown β-Ga2O3 epitaxial layer, thereby further reducing the defect density during gallium oxide epitaxy.

[0072] In one example, a third temperature-variable barrier layer 160 is formed on the second temperature-variable recrystallization layer 150. Exemplarily, the third temperature-variable barrier layer 160 includes, but is not limited to, β-Ga2O3. For example, a third temperature-variable barrier layer 160 is grown in an MOCVD reaction chamber at a growth pressure of 20 mbar-100 mbar, an oxygen to gallium molar flow rate ratio of 300-700, a carrier gas of high-purity nitrogen or high-purity argon, an oxygen source of high-purity oxygen or nitrous oxide, and a gallium source of trimethylgallium (TMGa) or triethylgallium (TEGa). The growth temperature (i.e., the temperature of the MOCVD reaction chamber) and growth time are varied and divided into three stages: the first stage growth temperature is 850℃-900℃, and the growth time is 5 min-10 min; the second stage growth temperature is 900℃-950℃, and the growth time is 10 min-15 min; the third stage growth temperature is 950℃-1000℃, and the growth time is 15 min-20 min. By growing at progressively higher temperatures in these three stages to form the final third temperature-variable barrier layer 160, the upward extension of defects can be more effectively restricted, thereby improving crystal quality. For example, as a combined embodiment, the growth temperature and growth time for the three stages of growing the third temperature-changing barrier layer 160 are 875°C and 7.5 min, 925°C and 12.5 min, and 975°C and 17.5 min, respectively.

[0073] In one example, such as Figure 2As shown, a third temperature-variable recrystallization layer 170 is formed on the third temperature-variable barrier layer 160. Exemplarily, the material of the third temperature-variable recrystallization layer 170 includes, but is not limited to, crystalline gallium oxide (Ga2O3). Exemplarily, the third temperature-variable recrystallization layer 170 is grown in an MOCVD reaction chamber at a growth pressure of 50 mbar-300 mbar, an oxygen to gallium molar flow ratio of 200-600, a carrier gas of high-purity nitrogen or high-purity argon, an oxygen source of high-purity oxygen or nitrous oxide, and a gallium source of trimethylgallium (TMGa) or triethylgallium (TEGa). The growth temperature and growth time are varied, divided into three stages: the first stage growth temperature is 950℃-1000℃, and the growth time is 1 min-5 min; the second stage growth temperature is 1000℃-1050℃, and the growth time is 1 min-5 min; the third stage growth temperature is 1050℃-1100℃, and the growth time is 5 min-10 min. For example, as a combined embodiment, during the growth of the third temperature-variable recrystallization layer 170, the growth temperatures and times for the three stages are 975°C and 3 min, 1025°C and 5 min, and 1075°C and 7.5 min, respectively. The final third temperature-variable recrystallization layer 170 is formed by increasing the temperature in three stages. The third temperature-variable barrier layer 160, combined with the third temperature-variable recrystallization layer 170, results in a three-stage temperature progression from low to high. This leads to good density and crystal quality in the subsequently grown β-Ga2O3 epitaxial layer, allowing defects to be redirected and annihilated at the growth interface to a greater extent. This more efficiently reduces the defect density during gallium oxide epitaxy, laying the foundation for the subsequent fabrication of power electronic devices.

[0074] In one example, such as Figure 2 As shown, a gallium oxide epitaxial layer 130 is formed on the third temperature-controlled recrystallization layer 170. Exemplarily, the material of the gallium oxide epitaxial layer 130 includes, but is not limited to, N-type β-Ga₂O₃. Exemplarily, the gallium oxide epitaxial layer 130 is grown in an MOCVD reaction chamber at a growth pressure of 30 mbar-80 mbar, a growth temperature of 750°C-900°C, a carrier gas of high-purity nitrogen or high-purity argon, an oxygen source of high-purity oxygen or nitrous oxide, a gallium source of trimethylgallium (TMGa) or triethylgallium (TEGa), a silicon source of tetraethoxysilane (TEOS), and a silicon doping concentration of 1E¹⁵ atoms / cm². 3 -1E17atoms / cm 3 The VI / III ratio is 300-800. For example, the thickness of the gallium oxide epitaxial layer 130 can be 0.2um-3um, such as 0.2um, 0.5um, 0.8um, 1um, 1.3um, 1.6um, 2um, 2.5um or 3um.

[0075] It should be noted that after the gallium oxide epitaxial layer 130 is grown, the temperature of the MOCVD reaction chamber is reduced to below 150°C to end the entire epitaxial growth process.

[0076] It is worth mentioning that the above steps are only examples, and the order of the steps can be adjusted without conflict.

[0077] Thus, the process steps of the semiconductor device manufacturing method according to an embodiment of this application are completed. It is understood that the semiconductor device manufacturing method of this embodiment includes not only the above steps, but may also include other necessary steps before, during or after the above steps, all of which are included in the scope of the manufacturing method of this embodiment.

[0078] In summary, the semiconductor device manufacturing method of this application can provide sufficient nucleation centers for the epitaxial growth of gallium oxide epitaxial layer by forming a temperature-variable barrier layer and a temperature-variable recrystallization layer between the substrate and the gallium oxide epitaxial layer, thereby improving the crystal quality of the gallium oxide epitaxial layer and reducing the defect density of the gallium oxide epitaxial layer, laying the foundation for the subsequent fabrication of power electronic devices.

[0079] The present invention has been described through the above embodiments. However, it should be understood that the above embodiments are for illustrative purposes only and are not intended to limit the invention to the scope of the described embodiments. Furthermore, those skilled in the art will understand that the present invention is not limited to the above embodiments, and many more variations and modifications can be made based on the teachings of the present invention, all of which fall within the scope of protection claimed by the present invention. The scope of protection of the present invention is defined by the appended claims and their equivalents.

Claims

1. A semiconductor device, characterized in that, include: Substrate; A first temperature-changing barrier layer is located on the substrate; The first temperature-variable recrystallization layer is located on the first temperature-variable barrier layer; A gallium oxide epitaxial layer is located on the first temperature-variable recrystallization layer.

2. The device as described in claim 1, characterized in that, Also includes: The second temperature-changing barrier layer is located on the first temperature-changing recrystallization layer; The second temperature-variable recrystallization layer is located on the second temperature-variable barrier layer; The third temperature-changing barrier layer is located on the second temperature-changing recrystallization layer; The third temperature-variable recrystallization layer is located on the third temperature-variable barrier layer.

3. A method for manufacturing a semiconductor device, characterized in that, include: A substrate is provided, and a first temperature-resistant barrier layer is formed on the substrate; A first temperature-variable recrystallization layer is formed on the first temperature-variable barrier layer; A gallium oxide epitaxial layer is formed on the first temperature-dependent recrystallization layer.

4. The manufacturing method as described in claim 3, characterized in that, The growth pressure for forming the first temperature-variable barrier layer is 20 mbar-100 mbar, the molar flow ratio of oxygen to gallium is 300-700, the carrier gas is high-purity nitrogen or high-purity argon, and the growth temperature and growth time include: The growth temperature in the first stage is 500℃-550℃, and the growth time is 1min-5min; The growth temperature in the second stage is 550℃-600℃, and the growth time is 3min-8min; The growth temperature in the third stage is 600℃-650℃, and the growth time is 5min-10min.

5. The manufacturing method as described in claim 3, characterized in that, The growth pressure for forming the first temperature-varying recrystallized layer is 50 mbar-300 mbar, the molar flow ratio of oxygen to gallium is 200-600, the carrier gas is high-purity nitrogen or high-purity argon, and the growth temperature and growth time include: The growth temperature in the first stage is 600℃-650℃, and the growth time is 1min-5min; The growth temperature in the second stage is 650℃-700℃, and the growth time is 1min-5min; The growth temperature in the third stage is 700℃-750℃, and the growth time is 5min-10min.

6. The manufacturing method as described in claim 3, characterized in that, Also includes: A second temperature-changing barrier layer is formed on the first temperature-changing recrystallization layer; A second temperature-variable recrystallization layer is formed on the second temperature-variable barrier layer; A third temperature-variable barrier layer is formed on the second temperature-variable recrystallization layer; A third temperature-variable recrystallization layer is formed on the third temperature-variable barrier layer.

7. The manufacturing method as described in claim 6, characterized in that, The growth pressure for forming the second temperature-variable barrier layer is 20 mbar-100 mbar, the molar flow ratio of oxygen to gallium is 300-700, the carrier gas is high-purity nitrogen or argon, and the growth temperature and growth time include: The growth temperature in the first stage is 700℃-750℃, and the growth time is 3min-8min; The growth temperature in the second stage is 750℃-800℃, and the growth time is 5min-10min; In the third stage, the growth temperature is 800℃-850℃ and the growth time is 10min-15min.

8. The manufacturing method as described in claim 6, characterized in that, The growth pressure for forming the second temperature-variable recrystallization layer is 50 mbar-300 mbar, the molar flow ratio of oxygen to gallium is 200-600, the carrier gas is high-purity nitrogen or high-purity argon, and the growth temperature and growth time include: The growth temperature in the first stage is 800℃-850℃, and the growth time is 1min-5min; The growth temperature in the second stage is 850℃-900℃, and the growth time is 1min-5min; The growth temperature in the third stage is 900℃-1000℃, and the growth time is 5min-10min.

9. The manufacturing method as described in claim 6, characterized in that, The growth pressure for forming the third temperature-variable barrier layer is 20 mbar-100 mbar, the molar flow ratio of oxygen to gallium is 300-700, the carrier gas is high-purity nitrogen or argon, and the growth temperature and growth time include: The growth temperature in the first stage is 850℃-900℃, and the growth time is 5min-10min; The growth temperature in the second stage is 900℃-950℃, and the growth time is 10min-15min; The growth temperature in the third stage is 950℃-1000℃, and the growth time is 15min-20min.

10. The manufacturing method as described in claim 6, characterized in that, The growth pressure for forming the third temperature-variable recrystallization layer is 50 mbar-300 mbar, the molar flow ratio of oxygen to gallium is 200-600, the carrier gas is high-purity nitrogen or argon, and the growth temperature and growth time include: The growth temperature in the first stage is 950℃-1000℃, and the growth time is 1min-5min; The growth temperature in the second stage is 1000℃-1050℃, and the growth time is 1min-5min; The growth temperature in the third stage is 1050℃-1100℃, and the growth time is 5min-10min.

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