Power semiconductor structure

Abstract

The invention provides a power semiconductor structure. The power semiconductor structure comprises a gallium-containing oxide substrate, a gallium-containing oxide semiconductor layer, a heat dissipation inner groove, a metal substrate and at least one pair of P-type semiconductor material and N-type semiconductor material. Wherein the gallium-containing oxide semiconductor layer is arranged on the gallium-containing oxide substrate. The heat dissipation inner trench surrounds the gallium-containing oxide semiconductor layer and is disposed on the gallium-containing oxide substrate. The metal substrate is connected to the heat dissipation inner groove in a heat conduction mode, and at least one pair of P-type semiconductor material and N-type semiconductor material is connected to the two ends of the metal substrate respectively. When an external current flows into the N-type semiconductor material and flows to the P-type semiconductor material through the metal substrate, heat energy generated by the gallium-containing oxide semiconductor layer is absorbed by the metal substrate through the heat dissipation inner groove, and then heat is released from the P-type semiconductor material and the N-type semiconductor material relative to one opposite end of the metal substrate.

Description

Technical Field

[0001] This invention relates to a power semiconductor structure, and more particularly to a gallium oxide semiconductor structure. Background Technology

[0002] Gallium oxide (Ga2O3) is an emerging wide-bandgap semiconductor material, particularly suitable for high-power and high-frequency applications. Compared to traditional silicon (Si), silicon carbide (SiC), and gallium nitride (GaN), gallium oxide has a higher breakdown electric field of approximately 8 MV / cm, more than 10 times that of Si, and its manufacturing cost is relatively low, making it highly promising for power electronic devices.

[0003] Gallium oxide (GaO) shows great promise in high-voltage power conversion, applicable to transformers, switching power supplies, inverters for electric vehicles, and high-voltage transmission systems. It also performs well in high-frequency applications in radar and microwave communication equipment. However, GaO power devices face significant thermal management challenges in high-power-density applications, primarily due to their relatively low thermal conductivity (approximately 10-30 W / m·K), far lower than that of conventional silicon (150 W / m·K), silicon carbide (120-270 W / m·K), and gallium nitride (130-230 W / m·K). This low thermal conductivity makes it difficult to dissipate heat quickly from the power device, affecting its reliability and lifespan. Therefore, the industry urgently needs an innovative power semiconductor structure to overcome the efficiency issues caused by the poor thermal conductivity of next-generation wide-bandgap semiconductor materials. Summary of the Invention

[0004] The main objective of this invention is to provide a power semiconductor structure having a gallium oxide substrate and related gallium oxide epitaxial semiconductor materials. Since this power semiconductor structure generates a large amount of heat during operation, the power semiconductor structure of this invention has an active cooling structure, which can achieve active heat dissipation by controlling the external current, quickly transferring the large amount of heat generated inside the power element to the outside, thereby improving the efficiency and reliability of the element.

[0005] To achieve the above objectives, the present invention provides a power semiconductor structure comprising a gallium oxide substrate, a gallium oxide semiconductor layer, a heat dissipation trench, a metal substrate, and at least one pair of P-type semiconductor materials and N-type semiconductor materials. The gallium oxide semiconductor layer is disposed on the gallium oxide substrate. The heat dissipation trench surrounds the gallium oxide semiconductor layer and is disposed on the gallium oxide substrate. The metal substrate is thermally connected to the heat dissipation trench, and at least one pair of P-type semiconductor materials and N-type semiconductor materials are respectively connected to both ends of the metal substrate. When an external current flows into the N-type semiconductor material and through the metal substrate to the P-type semiconductor material, the heat generated by the gallium oxide semiconductor layer is absorbed by the metal substrate through the heat dissipation trench, and then released by the P-type and N-type semiconductor materials at opposite ends of the metal substrate.

[0006] In one embodiment of the power semiconductor structure of the present invention, the gallium oxide substrate is a gallium monoxide (Ga2O3) substrate.

[0007] In one embodiment of the power semiconductor structure of the present invention, the gallium oxide (Ga2O3) substrate is a β-gallium oxide (β-Ga2O3) substrate.

[0008] In one embodiment of the power semiconductor structure of the present invention, the gallium oxide semiconductor layer is a gallium monoxide (Ga2O3) semiconductor layer.

[0009] In one embodiment of the power semiconductor structure of the present invention, the power semiconductor structure further includes a heat dissipation external trench, which is thermally connected to the opposite ends of the P-type semiconductor material and the N-type semiconductor material relative to the metal substrate.

[0010] In one embodiment of the power semiconductor structure of the present invention, the inner and outer heat dissipation trenches are filled with a thermally conductive filler selected from one or a combination thereof of diamond, aluminum nitride, and silicon dioxide.

[0011] In one embodiment of the power semiconductor structure of the present invention, at least one pair of P-type semiconductor materials and N-type semiconductor materials have multiple pairs of P-type semiconductor materials and N-type semiconductor materials, respectively connected to both ends of a metal substrate and disposed on at least one side of a heat dissipation inner trench.

[0012] In one embodiment of the power semiconductor structure of the present invention, at least one pair of P-type semiconductor materials and N-type semiconductor materials have multiple pairs of P-type semiconductor materials and N-type semiconductor materials, which are respectively connected to both ends of the metal substrate and are arranged around the periphery of the heat dissipation inner trench.

[0013] In one embodiment of the power semiconductor structure of the present invention, the power semiconductor structure further includes a heat dissipation ring, which is disposed around the periphery of the heat dissipation outer trench and is thermally connected to the heat dissipation outer trench.

[0014] To achieve the above objectives, the present invention provides a power semiconductor structure comprising a gallium monoxide (Ga2O3) substrate, an active region, a heat dissipation trench, a metal substrate, and at least one pair of P-type and N-type semiconductor materials. The active region is disposed on the gallium monoxide substrate. The heat dissipation trench surrounds the active region and is disposed on the gallium monoxide substrate. The metal substrate is thermally connected to the heat dissipation trench, and at least one pair of P-type and N-type semiconductor materials are respectively connected to both ends of the metal substrate. When an external current flows into the N-type semiconductor material and through the metal substrate to the P-type semiconductor material, the heat generated in the active region is absorbed by the metal substrate through the heat dissipation trench, and then released by the P-type and N-type semiconductor materials at opposite ends of the metal substrate.

[0015] In one embodiment of the power semiconductor structure of the present invention, the gallium oxide substrate is a β-gallium oxide (β-Ga2O3) substrate.

[0016] Other objects of the present invention, as well as the technical means and implementation methods of the present invention, will be understood by those skilled in the art upon referring to the accompanying drawings and the embodiments described below. Attached Figure Description

[0017] Figure 1 A schematic diagram of a power semiconductor structure according to an embodiment of the present invention is shown;

[0018] Figure 2 This shows a partially enlarged schematic diagram of an active cooling structure according to an embodiment of the present invention; and

[0019] Figure 3 This diagram shows a power semiconductor structure according to another embodiment of the present invention.

[0020] Explanation of reference numerals in the attached figures

[0021] 10 Gallium oxide substrates

[0022] 11 Active Area

[0023] 12 Heat dissipation internal trenches

[0024] 13 metal substrate

[0025] 14 N-type semiconductor materials

[0026] 15 P-type semiconductor materials

[0027] 16 External heat dissipation trenches

[0028] 17. Heat dissipation ring. Detailed Implementation

[0029] The following embodiments will explain the content of this invention. These embodiments are not intended to limit the implementation of this invention to any specific environment, application, or special method described in the embodiments. Therefore, the descriptions of the embodiments are merely illustrative of the invention and not intended to limit it. It should be noted that in the following embodiments and drawings, elements not directly related to this invention have been omitted and are not shown, and the dimensional relationships between the elements in the drawings are for ease of understanding only and are not intended to limit the actual scale.

[0030] This invention discloses a power semiconductor structure aimed at overcoming the problem of poor thermal management capabilities of power devices operating at high power density, thereby improving the reliability and lifespan of power devices. Please refer to... Figure 1 This displays a power semiconductor structure formed on a gallium oxide substrate 10. Specifically, the gallium oxide substrate 10 is an ultra-wide bandgap semiconductor material, such as gallium oxide (Ga₂O₃). Gallium oxide can be classified into α-Ga₂O₃, β-Ga₂O₃, γ-Ga₂O₃, δ-Ga₂O₃, and ε-Ga₂O₃ according to different crystal structures. Among the various gallium oxide crystal structures, β-Ga₂O₃ is the most stable crystal structure under normal temperature and pressure conditions, exhibiting excellent chemical stability. Currently, the vast majority of power devices developed in this field utilize β-Ga₂O₃. In terms of material properties, it is the only material that can be grown using fused deposition modeling, giving it a natural low-cost advantage and making it a major competitor for next-generation power devices.

[0031] Next, an active region 11 containing power elements is provided on the gallium oxide substrate 10. This active region 11 has a gallium oxide semiconductor layer, such as a gallium oxide (Ga2O3) semiconductor layer, which may vary depending on the power element. The power element may be a Schottky diode, a high electron mobility transistor, a metal-oxide-semiconductor field-effect transistor, a static induction transistor (SIT), a junction field-effect transistor (JFET), an insulated-gate bipolar transistor (IGBT), or a light-emitting diode (LED), etc. These power elements generate a large amount of heat in the active region 11 during operation. However, due to the low thermal conductivity of gallium oxide, to improve element performance and stability, this invention specifically provides a heat dissipation inner trench 12 surrounding the active region 11 and disposed on the gallium oxide substrate 10. The heat dissipation inner trench 12 is filled with a thermally conductive filler, which is a material with high thermal conductivity. This material may be selected from one or a combination of diamond, aluminum nitride, and silicon dioxide.

[0032] In addition, more specifically, the present invention provides an active cooling structure around the heat dissipation inner trench 12. In one embodiment of the present invention, this active cooling structure is an active cooling structure applying the Peltier effect; specifically, its basic architecture includes at least one metal substrate 13 and at least one pair of N-type semiconductor materials 14 and P-type semiconductor materials 15. Figure 1 As shown, at least one metal substrate 13 is disposed around the periphery of the heat dissipation inner trench 12, and the metal substrate 13 is thermally connected to the heat dissipation inner trench 12, which can quickly absorb a large amount of heat energy conducted to the heat dissipation inner trench 12 by the gallium oxide semiconductor layer 11. On the other hand, N-type semiconductor material 14 and P-type semiconductor material 15 are respectively connected to the two ends of a metal substrate 13 in pairs.

[0033] like Figure 1 As shown in the figure, multiple sets of active cooling structures are arranged around the periphery of the heat dissipation inner trench 12. Each set of active cooling structures includes a metal substrate 13 and a pair of N-type semiconductor materials 14 and P-type semiconductor materials 15. The pair of N-type semiconductor materials 14 and P-type semiconductor materials 15 are connected to both ends of the metal substrate 13 adjacent to the heat dissipation inner trench 12. Specifically, Figure 1 Multiple sets of active cooling structures are arranged around both sides of the heat dissipation trench 12. When the power element generates a large amount of heat in the active region 11 during operation, an external current can be introduced into the N-type semiconductor material 14, flowing through the metal substrate 13 to the P-type semiconductor material 15. According to the Peltier effect, the current flowing from the N-type semiconductor material 14 to the P-type semiconductor material 15 becomes a cold end, which can absorb heat. The heat generated by the gallium oxide semiconductor layer 11 will be absorbed by the metal substrate 13 through the heat dissipation trench 12, and then conducted to a proximal end of the N-type semiconductor material 14 and the P-type semiconductor material 15 connected to the metal substrate 13. Then, the N-type semiconductor material 14 and the P-type semiconductor material 15 will release heat from a opposite end (i.e., a distal end) of the metal substrate 13 relative to the N-type semiconductor material 14 and the P-type semiconductor material 15. It should be noted that the current between each set of active cooling structures is conducted through the metal substrate 13 connected in series at the distal ends of the N-type semiconductor material 14 and the P-type semiconductor material 15 (e.g., ...). Figure 2 The arrow shown represents the direction of current flow.

[0034] Please refer to both together. Figure 1 and Figure 2The power semiconductor structure of the present invention further includes a heat dissipation outer trench 16, which surrounds the periphery of the active cooling structure and is disposed on a gallium oxide substrate 10. This heat dissipation outer trench 16 can further absorb the heat energy absorbed by the active cooling structure. As shown in the figure, this heat dissipation outer trench 16 is connected to the opposite ends of the N-type semiconductor material 14 and the P-type semiconductor material 15 that release heat, so that the internal heat energy can be further transferred outward. Moreover, similar to the heat dissipation inner trench 12, the heat dissipation outer trench 16 is filled with a filling material with high thermal conductivity. The filling material can be selected from one or a combination of diamond, aluminum nitride, and silicon dioxide. On the other hand, as shown in the figure, a metal substrate 13 is further disposed between the heat dissipation outer trench 16 and the N-type semiconductor material 14 and the P-type semiconductor material 15. In addition to serving as a current connection between multiple sets of active cooling structures (e.g., Figure 2 In addition to the arrows shown (which represent the direction of current flow), heat conduction efficiency can be further improved.

[0035] Preferably, the present invention further includes a heat dissipation ring 17, which is arranged around the outer periphery of the heat dissipation outer groove 16 and thermally connected to the heat dissipation outer groove. Through the heat dissipation ring 17, which has a larger heat dissipation area, the large amount of heat generated inside the power component is further rapidly conducted outwards for heat dissipation. In practical applications, this heat dissipation ring 17 can be combined with other traditional heat dissipation structures such as heat sink fins to achieve the optimal heat dissipation path. On the other hand, Figure 1 The active cooling structure in the power semiconductor structure of this invention shown is for illustrative purposes only and is not intended to limit the invention. In practice, the number and layout of the active cooling structures between the inner and outer heat dissipation trenches around the active region can be adjusted according to actual needs. For example... Figure 3 As shown, multiple pairs of N-type semiconductor materials 14 and P-type semiconductor materials 15 are arranged around the heat dissipation inner trench 12 to facilitate the rapid dissipation of heat generated in the active region 11 to the heat dissipation outer trench 16 and heat dissipation ring 17 for external heat release.

[0036] The above embodiments are merely illustrative of implementation schemes of the present invention and to explain the technical features of the present invention, and are not intended to limit the scope of protection of the present invention. Any changes or equivalent arrangements that can be easily made by those skilled in the art are within the scope of the present invention, and the scope of protection of the present invention should be determined by the claims.

Claims

1. A power semiconductor structure comprising: A gallium oxide substrate; A gallium oxide semiconductor layer is disposed on the gallium oxide substrate; A heat dissipation trench surrounds the gallium oxide semiconductor layer and is disposed on the gallium oxide substrate; A metal substrate, thermally connected to the heat dissipation trench; and At least one pair of P-type semiconductor material and N-type semiconductor material are respectively connected to both ends of the metal substrate. in, When an external current flows into the N-type semiconductor material and through the metal substrate to the P-type semiconductor material, the heat generated by the gallium oxide semiconductor layer is absorbed by the metal substrate through the heat dissipation trench, and then released by the P-type semiconductor material and the N-type semiconductor material at opposite ends of the metal substrate.

2. The power semiconductor structure as claimed in claim 1, wherein the gallium-containing oxide substrate is a gallium monoxide substrate.

3. The power semiconductor structure as claimed in claim 2, wherein the gallium oxide substrate is a β-gallium oxide substrate.

4. The power semiconductor structure as claimed in claim 1, wherein the gallium-containing oxide semiconductor layer is a gallium monoxide semiconductor layer.

5. The power semiconductor structure as claimed in claim 1 further includes a heat dissipation external trench, thermally connected to the opposite ends of the P-type semiconductor material and the N-type semiconductor material relative to the metal substrate.

6. The power semiconductor structure of claim 5, wherein the inner and outer heat dissipation trenches are filled with a thermally conductive filler selected from one or a combination thereof of diamond, aluminum nitride, and silicon dioxide.

7. The power semiconductor structure as claimed in claim 1, wherein the at least one pair of P-type semiconductor materials and N-type semiconductor materials have multiple pairs of P-type semiconductor materials and N-type semiconductor materials, respectively connected to both ends of the metal substrate and disposed on at least one side of the heat dissipation inner trench.

8. The power semiconductor structure as claimed in claim 1, wherein the at least one pair of P-type semiconductor materials and N-type semiconductor materials have multiple pairs of P-type semiconductor materials and N-type semiconductor materials, respectively connected to both ends of the metal substrate and arranged around the periphery of the heat dissipation inner trench.

9. The power semiconductor structure as described in claim 5 further includes a heat dissipation ring, which is disposed around the periphery of the heat dissipation outer trench and is thermally connected to the heat dissipation outer trench.

10. A power semiconductor structure comprising: Gallium monoxide substrate; An active region is disposed on the gallium oxide substrate; A heat dissipation inner trench surrounds the active region and is disposed on the gallium oxide substrate; A metal substrate, thermally connected to the heat dissipation trench; and At least one pair of P-type semiconductor material and N-type semiconductor material are respectively connected to both ends of the metal substrate. in, When an external current flows into the N-type semiconductor material and through the metal substrate to the P-type semiconductor material, the heat generated in the active region is absorbed by the metal substrate through the heat dissipation trench, and then released by the P-type semiconductor material and the N-type semiconductor material at opposite ends of the metal substrate.

11. The power semiconductor structure of claim 10, wherein the gallium oxide substrate is a β-gallium oxide substrate.

Images