Epsilon-Ga2O3 / diamond heterojunction diode

Abstract

The invention belongs to the technical field of semiconductors, and provides an epsilon-Ga2O3 / diamond heterojunction diode. The epitaxial wafer comprises an anode metal layer, a p-type diamond substrate, an n-type epsilon-Ga2O3 epitaxial layer and a cathode metal layer which are stacked from bottom to top, when the substrate is composed of p-or p- / p + diamond, the epitaxial layer is composed of n-, n + or n- / n + type epsilon-Ga2O3, and the thickness of the layer composed of p-diamond is greater than or equal to 10 [mu] m; when the substrate is composed of p + diamond, the epitaxial layer is composed of n-or n- / n + type epsilon-Ga2O3, and the thickness of the layer composed of the n-type epsilon-Ga2O3 is 5-20 [mu] m. The epsilon-Ga2O3 disclosed by the invention can be directly subjected to heteroepitaxy on the diamond substrate, so that the size and the thickness of the thin film can be conveniently and directly regulated and controlled, and the manufacturing process is simplified; and the interface quality of the diode is relatively high, good rectification characteristics and kilovolt-level breakdown voltage are presented, and high interface thermal conductivity can be realized.

Description

Technical Field

[0001] This disclosure relates to the field of semiconductor technology, and more particularly to an ε-Ga2O3 / diamond heterojunction diode. Background Technology

[0002] Gallium oxide (Ga2O3), an ultrawide bandgap semiconductor material, possesses a wide bandgap (4.8 eV), high breakdown field strength (8 MV / cm), and good electron mobility (300 cm⁻¹). 2 Gallium oxide (GaO) has enormous application potential in power electronic devices. However, due to the limitations of p-type doping schemes and its low thermal conductivity, it needs to be heterogeneously integrated with other p-type wide-bandgap semiconductor materials to fully realize device performance. Common p-type doped wide-bandgap semiconductor materials include GaN, SiC, and diamond. Among them, diamond, with its ultra-wide bandgap of 5.5 eV and high thermal conductivity (>2000 W / m·K), has become an ideal material for integration with GaO.

[0003] β-Ga₂O₃, as the thermal equilibrium phase among the many crystalline phases of gallium oxide, is currently the only crystalline phase for gallium oxide single-crystal substrates. Although a few studies have attempted to directly epitaxially grow gallium oxide thin films on p-type diamond substrates, these films are generally polycrystalline or amorphous, and the heterojunction quality and device performance are significantly inferior to integrated devices based on β-Ga₂O₃ thin films. Therefore, existing high-quality diamond-based gallium oxide pn diodes are mainly based on β-Ga₂O₃ thin films.

[0004] Integration of β-Ga₂O₃ with diamond substrates has been proven to achieve high interfacial thermal conductivity and improve device heat dissipation. However, current diamond-based gallium oxide pn junction diodes face the following challenges in device fabrication and performance improvement: 1. As the primary crystalline phase currently integrated with diamond substrates, β-Ga₂O₃ is difficult to achieve single-orientation epitaxial growth on diamond substrates, primarily relying on mechanical lift-off or ion cutting for integration with p-type diamond substrates. However, the film size and thickness obtained through mechanical lift-off are difficult to control, and ion cutting suffers severe irradiation damage. Furthermore, both methods require additional transfer bonding processes for integration with the diamond substrate, increasing the fabrication complexity and difficulty of the diode device. 2. The current interface quality between diamond substrates and β-Ga₂O₃ films is poor, lacking good rectification characteristics and breakdown voltage performance. The breakdown voltage of diamond-based gallium oxide diodes is mostly below 500V. Therefore, it is necessary to provide a high-performance diamond-based gallium oxide pn junction diode. Summary of the Invention

[0005] This disclosure provides an ε-Ga2O3 / diamond heterojunction diode to at least solve the above-mentioned technical problems existing in the prior art.

[0006] According to a first aspect of the present disclosure, an ε-Ga2O3 / diamond heterojunction diode is provided, comprising an anode metal layer, a p-type diamond substrate, an n-type ε-Ga2O3 epitaxial layer, and a cathode metal layer stacked from bottom to top;

[0007] When the p-type diamond substrate is composed of a single layer of p - Diamond, double-layer p - / p + When any of the diamond compositions is used, the n-type ε-Ga2O3 epitaxial layer consists of a single layer of n - Type ε-Ga2O3, monolayer n + Type ε-Ga2O3, bilayer n - / n + Any composition of type ε-Ga2O3; at this time, the p-type diamond substrate contains p - The thickness of the diamond layer is ≥10μm;

[0008] When the p-type diamond substrate is composed of a single layer of p + When diamond is used, the n-type ε-Ga2O3 epitaxial layer consists of a single layer of n - Type ε-Ga2O3, bilayer n - / n + Any composition of type ε-Ga2O3; at this time, n in the n-type ε-Ga2O3 epitaxial layer - The thickness of the layer composed of ε-Ga2O3 is 5–20 μm.

[0009] Specifically, when the p-type diamond substrate is composed of a single layer of p - Diamond, double-layer p - / p + When any of the diamond compositions is used, the diode uses a p-type diamond substrate as the drift region to carry the breakdown voltage, requiring p... - The thickness of the diamond layer must not be less than 10 μm; when the p-type diamond substrate is composed of a single layer of p + When diamond is used, the diode uses an n-type ε-Ga2O3 epitaxial layer as the drift region to carry the withstand voltage, requiring n - The thickness of the layer composed of ε-Ga2O3 is relatively large, exceeding 5 μm. In this case, the p-type diamond substrate serves as both mechanical support and a conductive channel.

[0010] In the above scheme, when the p-type diamond substrate is composed of a single layer of p - Diamond, double-layer p - / p + When diamond has any of the following compositions, the p-type diamond substrate contains p - The thickness of the diamond layer is ≥10 μm. Preferably, in the p-type diamond substrate, p -The thickness of the diamond layer is 10–500 μm.

[0011] In one possible implementation, when the p-type diamond is composed of a single layer of p... - Diamond, double-layer p - / p + When any of the diamond compositions is used, the thickness of each layer in the n-type ε-Ga2O3 epitaxial layer is >10 nm.

[0012] In a preferred embodiment, when the p-type diamond substrate is composed of a single layer of p - Diamond, double-layer p - / p + When any of the diamond compositions are used, the thickness of each layer in the n-type ε-Ga2O3 epitaxial layer is 10 to 1000 nm.

[0013] In one possible implementation, when the p-type diamond substrate is composed of a single layer of p... - Diamond, double-layer p - / p + When diamond has any of the following compositions, the p-type diamond substrate contains p + The thickness of the diamond-composed layer is 1–500 μm.

[0014] In one possible implementation, when the p-type diamond substrate is composed of a single layer of p... + When diamond is used, the thickness of the p-type diamond substrate is 1–500 μm.

[0015] In a preferred embodiment, when the p-type diamond substrate is composed of a single layer of p + When diamond is used, the thickness of the p-type diamond substrate is 300–500 μm.

[0016] In one possible implementation, the single-layer p - The carrier concentration of the p-type diamond substrate composed of diamond is 1×10⁻⁶. 15 ~1×10 18 cm -3 The double-layer p - / p + In the p-type diamond substrate composed of diamond, p - The carrier concentration of the diamond-composed layer is 1×10⁻⁶. 15 ~1×10 18 cm -3 p + Carrier concentration of diamond-composed layers ≥ 1 × 10 18 cm -3 The single-layer p + The carrier concentration of the p-type diamond substrate composed of diamond is 1×10⁻⁶.18 ~1×10 21 cm -3 .

[0017] In one possible implementation, the single layer n - The carrier concentration of the n-type ε-Ga2O3 epitaxial layer composed of n-type ε-Ga2O3 is 1×10⁻⁶. 15 ~1×10 18 cm -3 The double-layer n - / n + In the n-type ε-Ga2O3 epitaxial layer composed of n-type ε-Ga2O3, n - The carrier concentration of the layer composed of ε-Ga₂O₃ is 1×10⁻⁶. 15 ~1×10 18 cm -3 n + The carrier concentration of the layer composed of ε-Ga₂O₃ is ≥1×10⁻⁶. 18 cm -3 The single layer n + The carrier concentration of the n-type ε-Ga2O3 epitaxial layer composed of n-type ε-Ga2O3 is 1×10⁻⁶. 18 ~1×10 21 cm -3 .

[0018] In one embodiment, the anode metal layer and the cathode metal layer are in ohmic contact with their respective adjacent layers.

[0019] In one embodiment, both the anode metal layer and the cathode metal layer are selected from at least one of Au, Al, Ni, Ti, Cu, and Pt layers.

[0020] According to one possible implementation of this disclosure, at least the following beneficial effects are achieved:

[0021] Unlike existing technologies that use β-Ga₂O₃ for transfer bonding integration on diamond substrates, the ε-Ga₂O₃ thin film selected in this disclosure can be directly heteroepitaxially grown on p-type diamond substrates. This allows for direct control of the film's size and thickness, effectively simplifying the fabrication process of diamond-based gallium oxide diodes. Furthermore, the heteroepitaxial diode of this disclosure exhibits high interface quality, demonstrating excellent rectification characteristics and kilovolt-level breakdown voltage, and achieves high interface thermal conductivity, effectively mitigating the self-heating effect during high-current operation.

[0022] It should be understood that the description in this section is not intended to identify key or essential features of the embodiments of this disclosure, nor is it intended to limit the scope of this disclosure. Other features of this disclosure will become readily apparent from the following description. Attached Figure Description

[0023] The above and other objects, features, and advantages of this disclosure will become readily apparent from the following detailed description of exemplary embodiments, taken in conjunction with the accompanying drawings. Several embodiments of this disclosure are illustrated in the drawings by way of example and not limitation, in which:

[0024] In the accompanying drawings, the same or corresponding reference numerals indicate the same or corresponding parts.

[0025] Figure 1 A schematic diagram of the ε-Ga2O3 / diamond heterojunction diode in Embodiment 1 of this disclosure is shown;

[0026] Figure 2 The X-ray diffraction (XRD) pattern of ε-Ga2O3 directly epitaxially grown on a (100) diamond substrate in Embodiment 1 of this disclosure is shown.

[0027] Figure 3 The reverse bias-current diagram of the diode device in Embodiment 1 of this disclosure is shown;

[0028] Figure 4 The XRD pattern of ε-Ga2O3 directly epitaxially grown on a (111) diamond substrate in Embodiment 2 of this disclosure is shown.

[0029] Figure 5 The XRD pattern of ε-Ga2O3 directly epitaxially grown on a polycrystalline diamond substrate in Embodiment 3 of this disclosure is shown.

[0030] Figure 6 A schematic diagram of the ε-Ga2O3 / diamond heterojunction diode in Comparative Example 1 of this disclosure is shown;

[0031] Figure 7 The reverse bias-current diagram of the diode device in Comparative Example 1 of this disclosure is shown;

[0032] Figure 8 The reverse bias-current diagram of the diode device in Comparative Example 2 of this disclosure is shown;

[0033] Figure 9 A schematic diagram of the ε-Ga2O3 / diamond heterojunction diode in Comparative Example 3 of this disclosure is shown;

[0034] Figure 10 The voltage-current diagram of the diode device in Comparative Example 3 of this disclosure is shown.

[0035] Figure label:

[0036] 1-Anode metal layer; 2-p + Layers composed of diamond; 3-p - Layers composed of diamond; 4-n- Layers composed of ε-Ga₂O₃; 5-n + A layer composed of ε-Ga2O3; a 6-cathode metal layer. Detailed Implementation

[0037] To make the objectives, features, and advantages of this disclosure more apparent and understandable, the technical solutions in the embodiments of this disclosure will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of this disclosure, and not all of them. All other embodiments obtained by those skilled in the art based on the embodiments of this disclosure without creative effort are within the scope of protection of this disclosure.

[0038] Example 1

[0039] This embodiment proposes an ε-Ga2O3 / diamond heterojunction diode, comprising, from bottom to top, an anode metal layer 1 (bottom electrode), a p-type diamond substrate ((100) crystal orientation), an n-type ε-Ga2O3 epitaxial layer, and a cathode metal layer 6 (top electrode). The specific structure is as follows: Figure 1 As shown, both the anode metal layer 1 and the cathode metal layer 6 are selected from Ti / Au bilayer;

[0040] p-type diamond substrate consists of a double-layer p-type diamond substrate. - / p + Composed of diamond, p + A diamond layer 2, with a thickness of 300 μm, is disposed on the anode metal layer 1, and has a carrier concentration of 1 × 10⁻⁶. 20 cm -3 ;p - Layer 3, composed of diamond, is set on p + Above layer 2, composed of diamond, is a layer 20 μm thick with a carrier concentration of 1 × 10⁻⁶. 16 cm -3 ;

[0041] The n-type ε-Ga2O3 epitaxial layer consists of a double n-type epitaxial layer. - / n + Composition of type ε-Ga2O3, n - Layer 4, composed of ε-Ga2O3, is disposed on p - Above layer 3, composed of diamond, the thickness is 0.4 μm, and the carrier concentration is 1 × 10⁻⁶. 18 cm -3 ;n + Layer 5, composed of ε-Ga2O3, is disposed on n - Above layer 4, composed of ε-Ga₂O₃, the thickness is 0.2 μm and the carrier concentration is 1 × 10⁻⁶. 19 cm -3 ;

[0042] The above-mentioned high carrier concentration n + Layer 5 and p of type ε-Ga2O3 + Layer 2, composed of diamond, is used to reduce ohmic contact resistance.

[0043] The X-ray diffraction (XRD) pattern of the above-mentioned ε-Ga2O3 directly epitaxially grown on a (100) diamond substrate is shown below. Figure 2 As shown, Figure 2 The diagram shows peaks for ε-Ga₂O₃ and (100) diamond, indicating that ε-Ga₂O₃ was successfully epitaxially grown on the (100) diamond substrate. The reverse bias-current plot of the aforementioned diode device is shown below. Figure 3 As shown, Figure 3 The results show that the diode device has good rectification characteristics and can reach a breakdown voltage in the kilovolt range, indicating that there is good interface quality between the diamond substrate and the ε-Ga2O3 epitaxial layer.

[0044] Example 2

[0045] This embodiment proposes an ε-Ga2O3 / diamond heterojunction diode, with a structure and parameters of each layer that are roughly the same as in Embodiment 1, except that the crystal orientation of the p-type diamond substrate in this embodiment is (111).

[0046] The XRD pattern of ε-Ga2O3 directly epitaxially grown on a (111) diamond substrate is shown below. Figure 4 As shown, Figure 4 The results show peaks for ε-Ga2O3 and (111) diamond, indicating that ε-Ga2O3 was successfully epitaxially grown on the (111) diamond substrate.

[0047] Example 3

[0048] This embodiment proposes an ε-Ga2O3 / diamond heterojunction diode, with a structure and parameters of each layer that are roughly the same as in Embodiment 1, except that the crystal orientation of the p-type diamond substrate in this embodiment is polycrystalline.

[0049] The XRD pattern of ε-Ga2O3 directly epitaxially grown on a polycrystalline diamond substrate is shown below. Figure 5 As shown, Figure 5 The results show that ε-Ga2O3 and (111), (220), (311), (100) and (400) diamond peaks appeared respectively, indicating that ε-Ga2O3 was successfully epitaxially grown on a polycrystalline diamond substrate.

[0050] Comparative Example 1

[0051] This comparative example presents an ε-Ga2O3 / diamond heterojunction diode, which differs from Example 1 in that the p-type diamond substrate in this comparative example consists of a single layer of p-type diamond substrate.+ Composed of diamond.

[0052] The diode comprises, from bottom to top, an anode metal layer 1 (bottom electrode), a p-type diamond substrate ((100) crystal orientation), an n-type ε-Ga2O3 epitaxial layer, and a cathode metal layer 6 (top electrode). The specific structure is as follows: Figure 6 As shown, both the anode metal layer 1 and the cathode metal layer 6 are selected from Ti / Au bilayer;

[0053] p-type diamond substrate consists of a single layer of p... + Composed of diamond, p + A diamond layer 2, with a thickness of 300 μm, is disposed on the anode metal layer 1, and has a carrier concentration of 1 × 10⁻⁶. 20 cm -3 ;

[0054] The n-type ε-Ga2O3 epitaxial layer consists of a double n-type epitaxial layer. - / n + Composition of type ε-Ga2O3, n - Layer 4, composed of ε-Ga2O3, is disposed on p + Above layer 2, composed of diamond, the thickness is 0.4 μm, and the carrier concentration is 1 × 10⁻⁶. 18 cm -3 ;n + Layer 5, composed of ε-Ga2O3, is disposed on n - Above layer 4, composed of ε-Ga₂O₃, the thickness is 0.2 μm and the carrier concentration is 1 × 10⁻⁶. 19 cm -3 .

[0055] The reverse bias-current diagram of the aforementioned diode device is as follows: Figure 7 As shown, Figure 7 The results show that the rectification characteristics of this diode device are reduced, and the breakdown voltage is also low, not reaching the kilovolt level.

[0056] Comparative Example 2

[0057] This comparative example presents an ε-Ga2O3 / diamond heterojunction diode, which differs from Example 1 in that the p-type diamond substrate in this comparative example consists of a single layer of p-type diamond substrate. + Composed of diamond, and the p + Diamond is polycrystalline.

[0058] The diode comprises, from bottom to top, an anode metal layer 1 (bottom electrode), a p-type diamond substrate (polycrystalline), an n-type ε-Ga2O3 epitaxial layer, and a cathode metal layer 6 (top electrode). The specific structure is as follows: Figure 6 As shown, both the anode metal layer 1 and the cathode metal layer 6 are selected from Ti / Au bilayer;

[0059] p-type diamond substrate consists of a single layer of p... + Diamond (polycrystalline) is composed of p + A diamond layer 2, with a thickness of 300 μm, is disposed on the anode metal layer 1, and has a carrier concentration of 1 × 10⁻⁶. 20 cm -3 ;

[0060] The n-type ε-Ga2O3 epitaxial layer consists of a double n-type epitaxial layer. - / n + Composition of type ε-Ga2O3, n - Layer 4, composed of ε-Ga2O3, is disposed on p + Above layer 2, composed of diamond, the thickness is 0.4 μm, and the carrier concentration is 1 × 10⁻⁶. 18 cm -3 ;n + Layer 5, composed of ε-Ga2O3, is disposed on n - Above layer 4, composed of ε-Ga₂O₃, the thickness is 0.2 μm and the carrier concentration is 1 × 10⁻⁶. 19 cm -3 .

[0061] The reverse bias-current diagram of the aforementioned diode device is as follows: Figure 8 As shown, Figure 8 The results show that the rectification characteristics of this diode device are reduced, and the breakdown voltage is also low, not reaching the kilovolt level.

[0062] As can be seen from the above Examples 1, 1, and 2, when the p-type diamond substrate of the diode is composed of a double-layer p... - / p + When diamond is used, the n-type ε-Ga2O3 epitaxial layer can consist of a single layer of n - Type ε-Ga2O3, monolayer n + Type ε-Ga2O3, bilayer n - / n + Any composition of type ε-Ga2O3, but in this case, p-type diamond substrate is required. - The thickness of the diamond layer must be ≥10μm, as in Example 1, to ensure the device has good rectification characteristics and achieves a breakdown voltage in the kilovolt range. When the p-type diamond substrate of the diode is composed of a single layer of p... + When diamond is used, the n-type ε-Ga2O3 epitaxial layer can consist of a single layer of n - Type ε-Ga2O3, bilayer n - / n + Any composition of type ε-Ga2O3, but in this case, n is required in the n-type ε-Ga2O3 epitaxial layer. - The thickness of the ε-Ga₂O₃ layer is between 5 and 20 μm, while in Comparative Examples 1 and 2, n- The thickness of the ε-Ga2O3 layer is only 0.4 μm, which is less than 5 μm. This will reduce the rectification characteristics and breakdown voltage of the device.

[0063] Comparative Example 3

[0064] This comparative example presents an ε-Ga2O3 / diamond heterojunction diode, which differs from Example 1 in that the diode in this comparative example does not include an n-type ε-Ga2O3 epitaxial layer, and the p-type diamond substrate consists of a single p-type diamond substrate. - Composed of diamond.

[0065] The diode comprises, from bottom to top, an anode metal layer 1 (bottom electrode), a p-type diamond substrate ((100) crystal orientation), and a cathode metal layer 6 (top electrode). The specific structure is as follows: Figure 9 As shown, both the anode metal layer 1 and the cathode metal layer 6 are selected from Ti / Au bilayer;

[0066] p-type diamond substrate consists of a single layer of p... - Composed of diamond, p - Layer 3, composed of diamond, is disposed on the anode metal layer 1, with a thickness of 300 μm and a carrier concentration of 1 × 10⁻⁶. 16 cm -3 .

[0067] The voltage-current diagram of the diode device mentioned above is as follows: Figure 10 As shown, Figure 10 The results show that the diamond substrate exhibits ohmic contacts, and the diode device has no rectification characteristics.

[0068] It should be understood that the various forms of processes shown above can be used to rearrange, add, or delete steps. For example, the steps described in this disclosure can be executed in parallel, sequentially, or in different orders, as long as the desired result of the technical solution of this disclosure can be achieved, and this is not limited herein.

[0069] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one of that feature. In the description of this disclosure, "a plurality of" means two or more, unless otherwise explicitly specified.

[0070] The above description is merely a specific embodiment of this disclosure, but the scope of protection of this disclosure is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the scope of the technology disclosed in this disclosure should be included within the scope of protection of this disclosure. Therefore, the scope of protection of this disclosure should be determined by the scope of the claims.

Claims

1. An ε-Ga2O3 / diamond heterojunction diode, characterized in that, The ε-Ga2O3 / diamond heterojunction diode comprises, from bottom to top, an anode metal layer, a p-type diamond substrate, an n-type ε-Ga2O3 epitaxial layer, and a cathode metal layer; When the p-type diamond substrate is composed of a single layer of p - Diamond, double-layer p - / p + When any of the diamond compositions is used, the n-type ε-Ga2O3 epitaxial layer consists of a single layer of n - Type ε-Ga2O3, monolayer n + Type ε-Ga2O3, bilayer n - / n + Any composition of type ε-Ga2O3; at this time, the p-type diamond substrate contains p - The thickness of the diamond layer is ≥10μm; When the p-type diamond substrate is composed of a single layer of p + When diamond is used, the n-type ε-Ga2O3 epitaxial layer consists of a single layer of n - Type ε-Ga2O3, bilayer n - / n + Any composition of type ε-Ga2O3; at this time, n in the n-type ε-Ga2O3 epitaxial layer - The thickness of the layer composed of ε-Ga2O3 is 5–20 μm.

2. The ε-Ga2O3 / diamond heterojunction diode according to claim 1, characterized in that, When the p-type diamond substrate is composed of a single layer of p - Diamond, double-layer p - / p + When diamond has any of the following compositions, the p-type diamond substrate contains p - The thickness of the diamond layer is 10–500 μm.

3. The ε-Ga2O3 / diamond heterojunction diode according to claim 1, characterized in that, When the p-type diamond is composed of a single layer of p - Diamond, double-layer p - / p + When any of the diamond compositions is used, the thickness of each layer in the n-type ε-Ga2O3 epitaxial layer is >10 nm.

4. The ε-Ga2O3 / diamond heterojunction diode according to claim 1, characterized in that, When the p-type diamond substrate is composed of a single layer of p - Diamond, double-layer p - / p + When any of the diamond compositions are used, the thickness of each layer in the n-type ε-Ga2O3 epitaxial layer is 10 to 1000 nm.

5. The ε-Ga2O3 / diamond heterojunction diode according to claim 1, characterized in that, When the p-type diamond substrate is composed of a single layer of p - Diamond, double-layer p - / p + When diamond has any of the following compositions, the p-type diamond substrate contains p + The thickness of the diamond-composed layer is 1–500 μm.

6. The ε-Ga2O3 / diamond heterojunction diode according to claim 1, characterized in that, When the p-type diamond substrate is composed of a single layer of p + When diamond is used, the thickness of the p-type diamond substrate is 1–500 μm.

7. The ε-Ga2O3 / diamond heterojunction diode according to claim 1, characterized in that, The single-layer p - The carrier concentration of the p-type diamond substrate composed of diamond is 1×10⁻⁶. 15 ~1×10 18 cm -3 The double-layer p - / p + In the p-type diamond substrate composed of diamond, p - The carrier concentration of the diamond-composed layer is 1×10 15 ~1×10 18 cm -3 p + Carrier concentration of diamond-composed layers ≥ 1 × 10⁻⁶ 18 cm -3 The single-layer p + The carrier concentration of the p-type diamond substrate composed of diamond is 1×10⁻⁶. 18 ~1×10 21 cm -3 .

8. The ε-Ga2O3 / diamond heterojunction diode according to claim 1, characterized in that, The single layer n - The carrier concentration of the n-type ε-Ga2O3 epitaxial layer composed of n-type ε-Ga2O3 is 1×10⁻⁶. 15 ~1×10 18 cm -3 The double-layer n - / n + In the n-type ε-Ga2O3 epitaxial layer composed of n-type ε-Ga2O3, n - The carrier concentration of the layer composed of ε-Ga₂O₃ is 1×10⁻⁶. 15 ~1×10 18 cm -3 n + The carrier concentration of the layer composed of ε-Ga₂O₃ is ≥1×10⁻⁶. 18 cm -3 The single layer n + The carrier concentration of the n-type ε-Ga2O3 epitaxial layer composed of n-type ε-Ga2O3 is 1×10⁻⁶. 18 ~1×10 21 cm -3 .

9. The ε-Ga2O3 / diamond heterojunction diode according to claim 1, characterized in that, The anode metal layer and the cathode metal layer are in ohmic contact with their respective adjacent layers.

10. The ε-Ga2O3 / diamond heterojunction diode according to claim 1, characterized in that, Both the anode metal layer and the cathode metal layer are selected from at least one of Au, Al, Ni, Ti, Cu, and Pt layers.

Images