Silicon carbide epitaxial furnace

Abstract

The utility model discloses a silicon carbide epitaxial furnace which comprises an outer cavity, a reaction cavity positioned in the outer cavity, a plurality of small discs positioned in the reaction cavity, an air inlet channel and an air exhaust channel, and a heating piece for heating the reaction cavity is also arranged in the outer cavity; the reaction cavity comprises a large disc located at the bottom, a circle of side wall surrounding the outer side of the large disc and a top plate connected with the top of the side wall, and the small disc is located on the large disc; the air inlet channel penetrates through the top of the outer cavity and the top plate to be communicated with the interior of the reaction cavity, and the exhaust channel penetrates through the bottom of the outer cavity and the large disc to be communicated with the reaction cavity. According to the utility model, a plurality of small discs are arranged on the large disc, and the large disc drives the small discs to rotate in the epitaxial process, so that a plurality of substrates can grow simultaneously, the growth efficiency is improved, and the uniformity of epitaxial layers of the small discs is ensured; by arranging the gas inlet channel and the gas exhaust channel in the vertical direction, reaction gas fully flows in the reaction cavity and makes contact with the substrate, the gas utilization rate is effectively increased, and the production cost is reduced.

Description

Technical Field

[0001] This utility model relates to the field of epitaxial growth technology, and in particular to a silicon carbide epitaxial furnace. Background Technology

[0002] Existing 6-inch silicon carbide epitaxial furnaces place the silicon carbide substrate inside a small graphite disk, which in turn rests on a larger graphite disk. These graphite components, including the large and small disks, together form the thermal field. The entire thermal field is housed within a quartz tube, surrounded by an electromagnetic heating coil. Heating occurs within the quartz tube, with the crucible temperature reaching over 1600°C. Under these conditions, silicon carbide crystals grow slowly along the substrate surface. However, due to the size limitations of the quartz tube and the reaction thermal field, only one silicon carbide substrate can be placed for epitaxial growth, resulting in low growth efficiency. Furthermore, existing epitaxial furnaces use horizontal gas inlet, with reactive gases entering from one side and exiting from the other. A large amount of the introduced MO source and other reactants are not fully utilized and are directly discharged into the exhaust gas treatment system. Utility Model Content

[0003] Purpose of the invention: In view of the shortcomings of existing silicon carbide epitaxial furnaces, which can only grow one substrate at a time and have low gas utilization, this utility model provides a silicon carbide epitaxial furnace that can grow multiple substrates simultaneously and effectively improve gas utilization.

[0004] Technical Solution: To solve the above problems, this utility model adopts a silicon carbide epitaxial furnace, including an outer chamber, a reaction chamber located inside the outer chamber, several small disks located inside the reaction chamber, an air inlet channel, and an exhaust channel. The outer chamber is also equipped with a heating element for heating the reaction chamber. The reaction chamber includes a large disk at the bottom, a ring of sidewalls surrounding the outer side of the large disk, and a top plate connected to the top of the sidewalls. The small disks are located on the large disk. A rotating shaft is connected to the center of the bottom of the large disk, and the rotating shaft is used to drive the large disk to rotate. The air inlet channel passes through the top of the outer chamber and the top plate and communicates with the inside of the reaction chamber. The exhaust channel passes through the bottom of the outer chamber and the large disk and communicates with the reaction chamber.

[0005] Furthermore, the several small disks are distributed equidistantly on the large disk in a circular pattern, and the small disks have grooves for placing the substrate.

[0006] Furthermore, the intake channel axis is perpendicular to the upper surface of the large disc, and the exhaust channel is coaxial with the rotating shaft.

[0007] Furthermore, the walls of the outer chamber are welded from double-layer stainless steel plates, and cooling water is circulated between the double-layer stainless steel plates to cool the reaction chamber.

[0008] Furthermore, the heating element is an electromagnetic coil.

[0009] Furthermore, the small disk is made of graphite.

[0010] Furthermore, the feature is that a gap is left between the small disc and the side wall for collecting the particulate matter generated by the reaction.

[0011] Beneficial effects: Compared with the prior art, the significant advantages of this utility model are (1) setting several small disks on a large disk, the large disk drives the small disks to rotate during the epitaxial process, so as to achieve the simultaneous growth of multiple substrates, improve the growth efficiency, and ensure the uniformity of the epitaxial layers of each small disk; (2) by setting vertical air intake and exhaust channels, the reaction gas can flow fully in the reaction chamber and contact the substrate, effectively improving the gas utilization rate and helping to reduce production costs. Attached Figure Description

[0012] Figure 1 This is a schematic diagram of the overall structure of the silicon carbide epitaxial furnace of this utility model. Detailed Implementation

[0013] like Figure 1 As shown, a silicon carbide epitaxial furnace in this embodiment includes an outer chamber 1, a reaction chamber located within the outer chamber 1, several small disks 3 located within the reaction chamber, an air inlet channel 8, and an exhaust channel 9. The outer chamber 1 is also equipped with a heating element 4 for heating the reaction chamber; the heating element 4 is an electromagnetic coil, and the reaction chamber is located above the heating element 4. The wall of the outer chamber 1 is welded from double-layer stainless steel plates, and cooling water is circulated between the double-layer stainless steel plates to cool the reaction chamber.

[0014] The reaction chamber includes a large disk 6 at the bottom, a ring of sidewalls 2 surrounding the outer side of the large disk 6, and a top plate 7 connected to the top of the sidewalls 2. Several small disks 3 are evenly distributed circumferentially on the large disk 6, and each small disk 3 has a groove for placing a substrate. The small disks 3 are made of graphite. A certain gap is left between the small disks 3 and the sidewalls 2, allowing particulate residues generated during the reaction to be blocked by the sidewalls and fall into the gaps, thus collecting the residues and not affecting the growth of the epitaxial wafer. A rotating shaft 5 is connected to the center of the bottom of the large disk 6, driving the large disk 6 to rotate. An air intake channel 8 passes through the top of the outer chamber 1 and the top plate 7, communicating with the interior of the reaction chamber. The axis of the air intake channel 8 is perpendicular to the upper surface of the large disk 6. In this embodiment, two symmetrical air intake channels 8 are provided. An exhaust channel 9 passes through the bottom of the outer chamber 1 and the large disk 6, communicating with the reaction chamber, and is coaxial with the rotating shaft 5.

[0015] This invention features a large disk with several smaller disks on it. During epitaxy, the large disk drives the smaller disks to rotate, enabling the simultaneous growth of multiple substrates, improving growth efficiency, and ensuring the uniformity of the epitaxial layers on each smaller disk. By setting vertical air intake and exhaust channels, the reaction gas can flow fully within the reaction chamber and come into contact with the substrate, effectively improving gas utilization and reducing production costs.

Claims

1. A silicon carbide epitaxial furnace, characterized in that, The device includes an outer chamber (1), a reaction chamber located within the outer chamber (1), several small discs (3) located within the reaction chamber, an air intake channel (8), and an exhaust channel (9). The outer chamber (1) is also equipped with a heating element (4) for heating the reaction chamber. The reaction chamber includes a large disc (6) located at the bottom, a ring of sidewalls (2) surrounding the outer side of the large disc (6), and a top plate (7) connected to the top of the sidewalls (2). The small discs (3) are located on the large disc (6). A rotating shaft (5) is connected to the center of the bottom of the large disc (6). The rotating shaft (5) is used to drive the large disc (6) to rotate. The air intake channel (8) passes through the top of the outer chamber (1) and the top plate (7) and communicates with the interior of the reaction chamber. The exhaust channel (9) passes through the bottom of the outer chamber (1) and the large disc (6) and communicates with the reaction chamber.

2. The silicon carbide epitaxial furnace as described in claim 1, characterized in that, The several small disks (3) are distributed equidistantly on the large disk (6) in a circle, and the small disks (3) have grooves for placing the substrate.

3. The silicon carbide epitaxial furnace as described in claim 1, characterized in that, The intake channel (8) is perpendicular to the upper surface of the large plate (6), and the exhaust channel (9) is coaxial with the rotating shaft (5).

4. The silicon carbide epitaxial furnace as described in claim 1, characterized in that, The wall of the outer chamber (1) is made of double-layer stainless steel plates welded together, and cooling water is passed between the double-layer stainless steel plates to cool the reaction chamber.

5. The silicon carbide epitaxial furnace as described in claim 1, characterized in that, The heating element (4) is an electromagnetic coil.

6. The silicon carbide epitaxial furnace as described in claim 1, characterized in that, The small plate (3) is made of graphite.

7. The silicon carbide epitaxial furnace as described in claim 1, characterized in that, A gap is left between the small disk (3) and the side wall (2) to collect the particulate matter produced by the reaction.

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