Special-shaped groove separation gate SIC-MOSFET structure

Abstract

The utility model provides a special-shaped groove separation gate SIC-MOSFET structure, belonging to the technical field of SiC, the special-shaped groove separation gate SIC-MOSFET structure comprises a groove forming part, a diversion channel part, a semiconductor layer, a source and drain region, a gate, an insulating layer and a heat dissipation part, the groove forming part is a groove formed on an SIC substrate through photoetching and corrosion, and the diversion channel part is arranged on the semiconductor layer. The trench forming part is used for controlling the electron flow velocity, the diversion channel part is connected with the trench forming part and the source and drain regions to form a diversion channel, the semiconductor layer covers the trench forming part and the diversion channel part and is used for forming an electron channel, the source and drain regions are arranged on the two sides of the semiconductor layer, and the semiconductor layer covers the diversion channel part and is used for forming an electron channel. The grid electrode is used for providing electrons and is arranged on the upper layer surface of the groove forming part; the utility model can keep stable work in severe environments such as high temperature, high pressure and the like, and solves the problem of thermal failure.

Description

Technical Field

[0001] The utility model belongs to the technical field of SIC, and in particular relates to a special-shaped trench separation gate SIC-MOSFET structure. Background Art

[0002] The SIC-MOSFET structure is a metal oxide semiconductor field effect transistor (MOSFET) based on silicon carbide (SiC) material. Compared with traditional silicon-based MOSFET, SiC-MOSFET has higher electron mobility, higher thermal conductivity and lower leakage current, which makes it have superior performance in high-power, high-temperature and high-frequency applications; when operating at high temperature, the stability of SiC-MOSFET depends on the characteristics of the material and the design of the device. SiC material has high thermal stability and high temperature resistance, which makes SiC-MOSFET have good stability at high temperature. However, some problems still occur at high temperature, such as thermal drift, thermal failure and material degradation; under high electric field, the migration of electrons in SiC-MOSFET may cause electron injection effect and hot electron effect, affecting the performance and reliability of the device. Utility Model Content

[0003] In view of this, the utility model provides a special-shaped trench separated gate SIC-MOSFET structure which can maintain stable operation in harsh environments such as high temperature and high voltage, and solve the problem of thermal failure.

[0004] The utility model is achieved in this way:

[0005] The utility model provides a special-shaped groove separated gate SIC-MOSFET structure, wherein the structure comprises a groove forming part, a guide channel part, a semiconductor layer, a source and drain region, a gate, an insulating layer and a heat dissipation part, wherein the groove forming part is a groove formed on a SIC substrate by photolithography and etching, the groove forming part is used to control the electron flow rate, the guide channel part is connected with the groove forming part and the source and drain region to form a guide channel, the semiconductor layer is covered and arranged on the groove forming part and the guide channel part to form an electron channel, the source and drain region are arranged on both sides of the semiconductor layer to provide electrons, the gate is arranged on the upper surface of the groove forming part to control the conduction and cutoff of the electron channel, the insulating layer is covered and arranged on the gate to isolate the gate from the semiconductor layer, the semiconductor layer is a SIC semiconductor material, and the source and drain region forms a PN junction with the semiconductor layer.

[0006] The utility model provides a special-shaped groove separated gate SIC-MOSFET structure with the following technical effects: through grooves and guide channels of various shapes, the electron flow rate is controlled, and the heat dissipation area is increased, and the heat dissipation efficiency is improved; by optimizing the groove shape, depth and guide channel shape, width, the electron flow rate and heat dissipation performance can be further improved; by setting an insulating layer, the control ability of the gate over the electron channel can be improved, and the gate and the semiconductor layer can be effectively isolated, and the leakage current of the electron channel can be reduced; it is ensured that the structure can maintain stable operation in harsh environments such as high temperature and high pressure, thereby improving the reliability and performance of the device.

[0007] On the basis of the above technical solution, the structure of a special-shaped trench separated gate SIC-MOSFET of the utility model can also be improved as follows:

[0008] The gate is made of metal material and is used to control the conduction and cutoff of the electron channel by applying voltage, and the insulating layer is made of high dielectric constant material and is used to improve the control ability of the gate over the electron channel.

[0009] Furthermore, the heat dissipation part includes heat dissipation windows on the upper and lower surfaces, and the surface of the heat dissipation window is a uniformly distributed concave-convex structure, and each groove is provided with a small hole.

[0010] The beneficial effect of adopting the above-mentioned improvement scheme is: by providing the heat dissipation window, the heat dissipation surface area is increased and the heat exchange efficiency with the surrounding environment is improved.

[0011] Furthermore, the heat dissipation portion also includes a heat sink, and the heat sink is connected to the heat dissipation window.

[0012] Furthermore, an upward protrusion is provided at the inner bottom end of the guide channel to reduce collision and scattering of electrons in the guide channel, thereby reducing fluctuations in electron flow velocity.

[0013] The beneficial effect of adopting the above-mentioned improvement scheme is that the protrusions can make electrons flow more smoothly and reduce the change in speed.

[0014] Furthermore, the groove cross-section of the groove forming portion is triangular, and the depth of the groove is between 50 nanometers and 500 nanometers.

[0015] The beneficial effects of adopting the above-mentioned improvement scheme are: by setting a triangular cross-section, a stronger electric field control capability can be provided; due to the sharp edges of the triangle, the electric field can act more concentratedly on the electron flow, thereby more effectively controlling the movement direction and speed of the electrons.

[0016] Furthermore, the triangle is an equilateral triangle.

[0017] Furthermore, the guide channel is linear in shape, and the width of the guide channel is between 30 nanometers and 300 nanometers.

[0018] Furthermore, the groove cross-section of the groove forming portion is U-shaped, and the depth of the groove is between 60 nanometers and 600 nanometers.

[0019] The beneficial effects of adopting the above-mentioned improvement scheme are: by setting the U-shaped cross section to have a larger surface area than the triangular cross section, the contact area between electrons and the groove surface is increased, and some specific physical effects are enhanced, such as enhancing the interaction between electrons and phonons.

[0020] Furthermore, the guide channel has a curved shape, and a width of the guide channel is between 30 nanometers and 300 nanometers.

[0021] Compared with the prior art, the utility model provides a special-shaped groove separated gate SIC-MOSFET structure with the following beneficial effects: through grooves and guide channels of various shapes, the electron flow rate is controlled, and the heat dissipation area is increased, and the heat dissipation efficiency is improved; by optimizing the groove shape, depth and guide channel shape, width, the electron flow rate and heat dissipation performance can be further improved; it is ensured that the structure can maintain stable operation in harsh environments such as high temperature and high pressure, thereby improving the reliability and performance of the device; by setting a heat dissipation window, it is used to increase the heat dissipation surface area and improve the heat exchange efficiency with the surrounding environment; by setting a protrusion, the electrons can flow more smoothly and the speed change can be reduced. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] In order to more clearly illustrate the technical solutions of the embodiments of the utility model, the drawings required for use in the description of the embodiments of the utility model will be briefly introduced below. Obviously, the drawings in the following description are only some embodiments of the utility model. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0023] Figure 1 A schematic diagram of a special-shaped trench split-gate SIC-MOSFET structure;

[0024] Figure 2 A schematic diagram of a first embodiment of a special-shaped trench split-gate SIC-MOSFET structure;

[0025] Figure 3 A schematic diagram of a second embodiment of a special-shaped trench split-gate SIC-MOSFET structure;

[0026] In the accompanying drawings, the components represented by the reference numerals are listed as follows:

[0027] 10. Groove forming portion; 11. Guide channel portion; 12. Semiconductor layer; 13. Source and drain regions; 14. Gate; 15. Insulating layer; 16. Heat dissipation portion; 17. Heat sink. DETAILED DESCRIPTION

[0028] In order to make the purpose, technical solution and advantages of the implementation mode of the present invention clearer, the technical solution in the implementation mode of the present invention will be clearly and completely described below in conjunction with the accompanying drawings in the implementation mode of the present invention.

[0029] Embodiment 1:

[0030] like Figure 1 , as shown in FIG. 2 , it is a first embodiment of a special-shaped trench separated gate SIC-MOSFET structure provided by the utility model. In this embodiment, it includes a groove forming portion 10, a guide channel portion 11, a semiconductor layer 12, a source and drain region 13, a gate 14, an insulating layer 15 and a heat dissipation portion 16. The groove forming portion 10 is a groove formed on the SIC substrate by photolithography and etching. The groove forming portion 10 is used to control the electron flow rate. The guide channel portion 11 is connected with the groove forming portion 10 and the source and drain region 13 to form a guide channel. The semiconductor layer 12 is covered on the groove forming portion 10 and the guide channel portion 11 to form an electron channel. The source and drain regions 13 are arranged on both sides of the semiconductor layer 12 to provide electrons. The gate 14 is arranged on the upper surface of the groove forming portion 10 to control the conduction and cutoff of the electron channel. The insulating layer 15 is covered on the gate 14 to isolate the gate 14 from the semiconductor layer 12. The semiconductor layer 12 is a SIC semiconductor material. The source and drain regions 13 and the semiconductor layer 12 form a PN junction.

[0031] The semiconductor layer 12 is made of SIC semiconductor material, which has good electrical conductivity and thermal conductivity. The source and drain regions 13 are made of N-type or P-type SIC material, and form a PN junction with the semiconductor layer 12 .

[0032] When in use, the electron flow rate is adjusted by controlling the voltage of the gate 14, and the electron flow rate is optimized according to the special groove shape, depth, and guide channel shape and width. The heat dissipation surface area is increased through the heat dissipation part to promote heat conduction and heat dissipation, thereby further improving the heat dissipation effect.

[0033] Furthermore, in the above technical solution, an upward protrusion is provided at the inner bottom end of the guide channel to reduce collision and scattering of electrons in the guide channel, thereby reducing fluctuations in electron flow rate.

[0034] Furthermore, in the above technical solution, the groove cross-section of the groove forming portion 10 is triangular, and the depth of the groove is between 50 nanometers and 500 nanometers.

[0035] Among them, the triangular cross-section is more inclined to reduce the scattering and influence of the surface on the electrons, reduce the collision of the electrons in the groove, and make the electrons flow more smoothly through the groove forming portion 10, thereby further stabilizing the electron flow rate.

[0036] Furthermore, in the above technical solution, the shape of the guide channel is linear, and the width of the guide channel is between 30 nanometers and 300 nanometers.

[0037] Furthermore, in the above technical solution, the triangle is an equilateral triangle.

[0038] Embodiment 2:

[0039] like Figure 1 , shown in FIG3 , is a second embodiment of a special-shaped trench separated gate SIC-MOSFET structure provided by the utility model. In this embodiment, the cross-sectional shape of the trench forming portion 10 is U-shaped, and the depth of the trench is between 60 nanometers and 600 nanometers.

[0040] Among them, since the U-shaped cross-section is relatively flat, the movement of electrons in the groove is smoother, reducing the speed loss of electrons and helping to maintain a more stable electron flow rate.

[0041] Among them, the edge of the U-shaped cross-section will produce a stronger local electric field effect, which can be used for specific applications, such as local electric field regulation or electron beam focusing.

[0042] In this embodiment, the guide channel is in a curved shape, and the width of the guide channel is between 30 nanometers and 300 nanometers.

[0043] Among them, in the above technical solution, the gate 14 is a metal material, which is used to control the conduction and cutoff of the electron channel by applying voltage, and the insulating layer 15 is a high dielectric constant material, which is used to improve the control ability of the gate 14 on the electron channel.

[0044] Furthermore, in the above technical solution, the heat dissipation portion 16 includes heat dissipation windows on the upper and lower surfaces, and the surface of the heat dissipation window is a uniformly distributed concave-convex structure, and each concave groove is provided with a small hole.

[0045] Furthermore, in the above technical solution, the heat dissipation portion 16 further includes a heat sink 17, and the heat sink 17 is connected to the heat dissipation window.

[0046] Among them, the heat sink 17 is connected to the heat dissipation window and dissipates heat by heat conduction convection. When in use, the air will naturally convect around it. The heat dissipation window can promote air flow and use natural convection to dissipate heat.

[0047] Specifically, the principle of the utility model is: when in use, the electron flow rate is adjusted by controlling the voltage of the gate 14, and the electron flow rate is optimized according to the special groove shape, depth and the shape and width of the guide channel, and the heat dissipation surface area is increased through the heat dissipation part to promote heat conduction and heat dissipation, thereby further improving the heat dissipation effect; when in use, the air will naturally convect around, the heat dissipation window can promote air flow, and use natural convection to dissipate heat.

Claims

1. A special-shaped trench split-gate SIC-MOSFET structure, characterized in that: The invention comprises a groove forming part (10), a flow guiding channel part (11), a semiconductor layer (12), a source and drain region (13), a gate (14), an insulating layer (15) and a heat dissipation part (16), wherein the groove forming part (10) is a groove formed on a SIC substrate by photolithography and etching, the groove forming part (10) is used to control the electron flow rate, the flow guiding channel part (11) is connected with the groove forming part (10) and the source and drain region (13) to form a flow guiding channel, and the semiconductor layer (12) is arranged on the groove forming part (10) and the flow guiding channel part (11). The channel portion (11) is used to form an electron channel, the source and drain regions (13) are arranged on both sides of the semiconductor layer (12) to provide electrons, the gate (14) is arranged on the upper surface of the groove forming portion (10) to control the conduction and cutoff of the electron channel, the insulating layer (15) is covered on the gate (14) to isolate the gate (14) from the semiconductor layer (12), the semiconductor layer (12) is a SIC semiconductor material, and the source and drain regions (13) and the semiconductor layer (12) form a PN junction.

2. The special-shaped trench split-gate SIC-MOSFET structure according to claim 1, characterized in that: The gate (14) is made of metal material and is used to control the conduction and cutoff of the electron channel by applying voltage. The insulating layer (15) is made of high dielectric constant material and is used to improve the control capability of the gate (14) over the electron channel.

3. The special-shaped trench split-gate SIC-MOSFET structure according to claim 2, characterized in that: The heat dissipation portion (16) comprises heat dissipation windows on the upper and lower surfaces, the surface of the heat dissipation window being a uniformly distributed concave-convex structure, and each concave groove is provided with a small hole.

4. The special-shaped trench split-gate SIC-MOSFET structure according to claim 3, characterized in that: The heat dissipation portion (16) further comprises a heat dissipation fin (17), and the heat dissipation fin (17) is connected to the heat dissipation window.

5. The special-shaped trench split-gate SIC-MOSFET structure according to claim 4, characterized in that: An upward protrusion is provided at the inner bottom end of the guide channel to reduce the collision and scattering of electrons in the guide channel, thereby reducing the fluctuation of the electron flow rate.

6. The special-shaped trench split-gate SIC-MOSFET structure according to claim 5, characterized in that: The groove cross-section of the groove forming portion (10) is triangular, and the depth of the groove is between 50 nanometers and 500 nanometers.

7. The special-shaped trench split-gate SIC-MOSFET structure according to claim 6, characterized in that: The triangle is an equilateral triangle.

8. The heterogeneous trench split-gate SIC-MOSFET structure according to claim 7, characterized in that: The guide channel is in a linear shape, and the width of the guide channel is between 30 nanometers and 300 nanometers.

9. The heterogeneous trench split-gate SIC-MOSFET structure according to claim 5, characterized in that: The groove cross-section of the groove forming portion (10) is U-shaped, and the depth of the groove is between 60 nanometers and 600 nanometers.

10. The special-shaped trench split-gate SIC-MOSFET structure according to claim 9, characterized in that: The guide channel has a curved shape, and a width of the guide channel is between 30 nanometers and 300 nanometers.

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