TWI818661B - Single crystal furnace - Google Patents

Abstract

The invention relates to a single crystal furnace, which includes a furnace body. A crucible is provided in a cavity defined by the furnace body. An exhaust port connected to an exhaust pipe is provided at the bottom of the furnace body. The exhaust port is provided with a device to prevent leakage of the crucible. The silicon melt enters the first protective structure of the exhaust port.

Description

Single crystal furnace

The invention belongs to the technical field of silicon wafer product production, and particularly relates to a single crystal furnace.

When producing single crystal ingots, the method of filling polycrystalline silicon into a quartz crucible, then melting the polycrystalline silicon, stabilizing the temperature of the melt, and then growing the ingot by bringing the seed crystal into contact with the melt is widely used. During the melting process of polycrystalline silicon, the polycrystalline silicon suddenly sinks or tilts sideways, or due to technical instability during the crystal rod growth process, the crystal rod falls and impacts the quartz crucible, thus causing cracks in the quartz crucible and causing cracks inside the quartz crucible. Accidents of silicon melt leakage occur from time to time. If the silicon melt leaks, the insulation material at the bottom of the equipment, the exhaust pipe, and the crucible mechanism will be seriously damaged.

In order to solve the above technical problems, the present invention provides a single crystal furnace to solve problems such as damage to crystal ingot production components caused by leakage of silicon melt.

In order to achieve the above object, the technical solution adopted in the embodiment of the present invention is: a single crystal furnace, including a furnace body, a crucible is provided in a cavity defined by the furnace body, and an exhaust gas connected to the exhaust pipe is provided at the bottom of the furnace body. The exhaust port is provided with a first protective structure to prevent the leaked silicon melt from the crucible from entering the exhaust port.

Optionally, the first protective structure includes an extension sleeve sleeved on the exhaust port.

Optionally, an end of the extension sleeve away from the exhaust port is provided with an outwardly extending flange.

Optionally, the extension sleeve is a telescopic sleeve.

Optionally, the inner wall of the exhaust pipe is provided with a buffer structure that slows down the flow rate of the silicon melt.

Optionally, the buffer structure includes a plurality of baffle plates spaced and staggered along the extension direction of the exhaust pipe, and a plurality of the baffle plates are included in the extension direction of the exhaust pipe. The adjacent first baffle and the second baffle, the orthographic projection of the first baffle in the extension direction of the exhaust pipe, and the orthographic projection of the second baffle in the extension direction of the exhaust pipe overlap.

Optionally, along the extension direction of the exhaust pipe, a plurality of the baffle plates are arranged in a spiral shape around the inner wall of the exhaust pipe.

Optionally, the end of the baffle plate away from the inner wall of the exhaust pipe is inclined and extended in a direction close to the exhaust port.

Optionally, a crucible shaft is passed through the center of the bottom of the furnace body. The crucible is fixed on one end of the crucible shaft away from the bottom of the furnace body. The crucible shaft is covered with a sleeve to prevent the silicon melt from leaking from flowing into the furnace body. The bottom of the furnace body is a second protective structure on one side away from the crucible.

Optionally, the second protective structure includes a protective sleeve placed on the outside of the crucible shaft. The protective sleeve includes a first part close to the bottom of the furnace body and a second part far away from the bottom of the furnace body. The second part The inner wall of the second part is in close contact with the crucible shaft. The outer wall of the second part is a curved structure serving as a guide surface. The area of the end surface of the second part away from the first part is smaller than the end of the second part close to the first part. The area of the end face.

Optionally, the first part is a scalable structure.

The beneficial effect of the present invention is: through the arrangement of the first protective structure, leaked silicon melt is prevented from entering the exhaust pipe.

In order to help the review committee understand the technical features, content and advantages of the present invention and the effects it can achieve, the present invention is described in detail below in the form of embodiments with the accompanying drawings and attachments, and the drawings used therein are , its purpose is only for illustration and auxiliary description, and may not represent the actual proportions and precise configurations after implementation of the present invention. Therefore, the proportions and configuration relationships of the attached drawings should not be interpreted or limited to the actual implementation of the present invention. The scope shall be stated first.

In the description of the embodiments of the present invention, it should be understood that the terms "length", "width", "upper", "lower", "front", "back", "left", "right", "vertical" ", "horizontal", "top", "bottom", "inner", "outer", etc. indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings, and are only for convenience and simplicity in describing the embodiments of the present invention. The description does not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operate in a specific orientation, and therefore is not to be construed as a limitation of the invention.

In addition, the terms “first” and “second” are used for descriptive purposes only and cannot be understood as indicating or implying relative importance or implicitly indicating the quantity of indicated technical features. Thus, features defined as “first” and “second” may explicitly or implicitly include one or more of the described features. In the description of the embodiments of the present invention, "plurality" means two or more than two, unless otherwise explicitly and specifically limited.

In the embodiments of the present invention, unless otherwise expressly stipulated and limited, the terms "installation", "connection", "connection", "fixing" and other terms should be understood in a broad sense. For example, it can be a fixed connection or a removable connection. Disassembly and connection, or integration; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium; it can be an internal connection between two elements or an interaction between two elements. For those with ordinary knowledge in the art, the specific meanings of the above terms in the embodiments of the present invention can be understood according to specific circumstances.

Referring to FIG. 1 , the silicon melt 100 leaks, and most of the silicon melt 100 flows into the crucible shaft 40 and the exhaust pipe 2 , causing damage to the exhaust pipe 2 and the mechanical structure located below the crucible shaft 40 .

Referring to Figure 2, to address the above problems, this embodiment provides a single crystal furnace, which includes a furnace body 10. A crucible 30 is provided in a chamber 20 defined by the furnace body 10, and an exhaust pipe 2 is provided at the bottom of the furnace body 10. A connected exhaust port is provided with a first protective structure 50 to prevent silicon melt leaked from the crucible 30 from entering the exhaust port.

If the silicon melt leaks, most of it will flow into the exhaust port and into the exhaust pipe 2, thereby causing damage to the exhaust pipe 2. The first protective structure 50 is provided to prevent the silicon melt from entering the exhaust port, thereby causing damage to the exhaust pipe 2. The exhaust pipe 2 plays a protective role.

The first protective structure 50 can have a variety of specific structural forms, as long as it can prevent the silicon melt from entering the exhaust port. In some implementations of this embodiment, the first protective structure 50 includes a structure that is sleeved on the exhaust port. Extension sleeve over the mouth.

The arrangement of the extension sleeve increases the height of the exhaust port. If the silicon melt leaks, the arrangement of the extension sleeve prevents the silicon melt from flowing into the exhaust port.

For example, the edge of the extension sleeve and the exhaust port is an integral structure, which increases the sealing between the extension sleeve and the exhaust port.

In some implementations of this embodiment, in order to further effectively prevent the silicon melt from flowing into the exhaust port, an outwardly extending flange 51 is provided at one end of the extension sleeve away from the exhaust port.

In some implementations of this embodiment, the extension sleeve is a telescopic sleeve.

Silicon melt leakage occurs at different stages, the volume of the leaked silicon melt is different, and the capacity of the silicon melt that can be accommodated by different crucibles 30 is also different, the height of the extension sleeve can be adjusted adaptively to effectively prevent leakage. The silicon melt flows into the exhaust port.

The telescopic sleeve may have a variety of specific structural forms. For example, the extension sleeve may include a plurality of telescopically arranged sub-sleeves connected by sleeves. The extension sleeve may also include a folding wall and a telescopic rod. The telescopic rod telescopes to expand or fold the folding wall, thereby adjusting the height of the extension sleeve.

In some implementations of this embodiment, the inner wall of the exhaust pipe 2 is provided with a buffer structure that slows down the flow rate of the silicon melt.

When the silicon melt flows into the exhaust pipe 2 , the buffer structure slows down the flow rate of the silicon melt and gradually solidifies, thereby reducing damage to the exhaust pipe 2 .

The buffer structure may have a variety of specific structural forms. In some implementations of this embodiment, the buffer structure includes a plurality of buffer structures spaced apart along the extension direction of the exhaust pipe 2 and staggered on the inner wall of the exhaust pipe 2 . Baffle plates 60, a plurality of the baffle plates 60 include first baffle plates and second baffle plates adjacent in the extension direction of the exhaust pipe 2, the first baffle plate in the extension direction of the exhaust pipe 2 The orthographic projection partially overlaps with the orthographic projection of the second baffle in the extension direction of the exhaust pipe 2 .

The arrangement of multiple blocking plates 60 slows down the flow rate of the silicon melt and prolongs the flow time of the silicon melt, thereby causing the silicon melt to gradually solidify during the circulation process and preventing the silicon melt from further flowing into other areas and causing damage to other parts. damage.

For example, the exhaust pipe 2 includes a first area close to the exhaust port, and the buffer structure is disposed in the first area to minimize damage to components such as the exhaust pipe 2 by the silicon melt.

In some implementations of this embodiment, along the extension direction of the exhaust pipe 2, a plurality of the baffle plates 60 are arranged in a spiral shape around the inner wall of the exhaust pipe 2.

The position where the silicon melt enters the exhaust pipe 2 from the exhaust port is not necessarily fixed, and the cross-section of the exhaust pipe 2 is annular. In order to effectively prevent the silicon melt, multiple blocking plates 60 are provided. They are arranged in a spiral shape on the inner wall of the exhaust pipe 2 .

In some implementations of this embodiment, the end of the baffle plate 60 away from the inner wall of the exhaust pipe 2 is inclined and extended in a direction close to the exhaust port.

The obliquely arranged blocking plate 60 can effectively extend the time for the silicon melt to flow into the next blocking plate 60, effectively slow down the flow rate of the silicon melt, shorten the area where the silicon melt flows through the exhaust pipe 2, and effectively protect Exhaust pipe 2 and other components.

In some implementations of this embodiment, a crucible shaft 40 is passed through the center of the bottom of the furnace body 10 , and the crucible 30 is fixed at one end of the crucible shaft 40 away from the bottom of the furnace body 10 . The crucible shaft 40 is sleeved with There is a second protective structure 70 on the side of the bottom of the furnace body 10 away from the crucible 30 to prevent the leaked silicon melt from the crucible 30 from flowing into the furnace body 10 .

If the silicon melt leaks, part of the silicon melt will flow through the crucible shaft 40 and flow from the crucible shaft 40 into the mechanical structure on the side of the bottom of the furnace body 10 away from the crucible 30 (such as lifting, rotating, etc. mechanical structures) , and cause damage to it. The arrangement of the second protective structure 70 prevents the silicon melt from flowing into the side of the bottom of the furnace body 10 away from the crucible 30 and to the machinery located on the side of the bottom of the furnace body 10 away from the crucible 30 . The structure plays a protective role.

The second protective structure 70 can have a variety of specific structural forms. In some implementations of this embodiment, the second protective structure 70 includes a protective sleeve set on the outside of the crucible shaft 40 , and the protective sleeve includes a protective sleeve close to the furnace. The first part of the bottom of the body 10 and the second part away from the bottom of the furnace body 10. The inner wall of the second part is in close contact with the crucible shaft 40. The outer wall of the second part is a curved surface structure serving as a guide surface. The area of the end surface of the second part away from the first part is smaller than the area of the end surface of the second part close to the first part.

The protective sleeve is arranged so that the leaked silicon melt flows to the periphery of the crucible shaft 40 through the guide surface, and prevents the leaked silicon melt from flowing along the crucible shaft 40 into the side of the bottom of the furnace body 10 away from the crucible 30 .

In this embodiment, the protective sleeve is in close contact with the crucible shaft 40 to effectively guide the leaked silicon melt into the periphery of the crucible shaft 40 .

For example, the cross section of the second part of the protective sleeve in the extending direction of the crucible shaft 40 is a symmetrically arranged triangle.

In some implementations of this embodiment, the first part is a retractable structure.

The arrangement of the telescopic structure can adjust the relative positional relationship between the second part of the protective sleeve and the crucible shaft 40 to more effectively prevent the leaked silicon melt from flowing into the bottom of the furnace body 10 away from the crucible 30 side.

The telescopic structure may have various specific structural forms. For example, the first part includes a telescopic rod.

The above are only preferred embodiments of the present invention and are not intended to limit the implementation scope of the present invention. If the present invention is modified or equivalently substituted without departing from the spirit and scope of the present invention, the protection shall be covered by the patent scope of the present invention. within the range.

2:Exhaust pipe 10: Furnace body 20: Chamber 30:Crucible 40: Crucible shaft 50:First protective structure 51:Flange 60:Blocking plate 70: Second protective structure step

Figure 1 shows a schematic diagram of the state of silicon melt leakage in the related art; Figure 2 shows a schematic structural diagram of a single crystal furnace in an embodiment of the present invention.

2:Exhaust pipe

10: Furnace body

20: Chamber

30:Crucible

40: Crucible shaft

50:First protective structure

51:Flange

60:Blocking plate

70: Second protective structure step

Claims (5)

A single crystal furnace includes a furnace body. A crucible is provided in a cavity defined by the furnace body. An exhaust port connected to an exhaust pipe is provided at the bottom of the furnace body. A silicon melt is provided on the exhaust port to prevent leakage of the crucible. Enter the first protective structure of the exhaust port; the first protective structure includes an extension sleeve sleeved on the exhaust port; the extension sleeve is a telescopic sleeve; the inner wall of the exhaust pipe is provided with A buffer structure that slows down the flow rate of the silicon melt; the buffer structure includes a plurality of baffle plates spaced along the extension direction of the exhaust pipe and staggered on the inner wall of the exhaust pipe, and the plurality of baffle plates are included in the exhaust pipe. The first baffle and the second baffle are adjacent in the extension direction of the exhaust pipe, the orthographic projection of the first baffle in the extension direction of the exhaust pipe, and the orthographic projection of the second baffle in the extension direction of the exhaust pipe. The orthographic projections on the exhaust pipe partially overlap; along the extension direction of the exhaust pipe, a plurality of the blocking plates are arranged in a spiral shape on the inner wall of the exhaust pipe; one end of the blocking plate is away from the inner wall of the exhaust pipe It is arranged to extend obliquely in the direction close to the exhaust port. The single crystal furnace of claim 1, wherein an end of the extension sleeve away from the exhaust port is provided with an outwardly extending flange. The single crystal furnace as described in claim 1, wherein a crucible shaft is passed through the center of the bottom of the furnace body, and the crucible is fixed on one end of the crucible shaft away from the bottom of the furnace body, and a protective ring is set on the crucible shaft. The silicon melt leaked from the crucible flows into the second protective structure on the side of the bottom of the furnace body away from the crucible. The single crystal furnace according to claim 3, wherein the second protective structure includes a protective sleeve placed on the outside of the crucible shaft, and the protective sleeve includes a first part close to the bottom of the furnace body and a first part away from the furnace body. The second part of the bottom, the inner wall of the second part is in close contact with the crucible shaft, the outer wall of the second part is a curved structure serving as a guide surface, and the area of the end surface of the second part away from the first part is smaller than the The area of the end surface of the second part adjacent to one end of the first part. The single crystal furnace according to claim 4, wherein the first part is a retractable structure.