Side-opening resistance silicon carbide single crystal growth furnace

Abstract

This invention belongs to the technical field of single crystal growth equipment, specifically relating to a side-opening resistance-type silicon carbide single crystal growth furnace. It includes a frame, on which a growth furnace body is mounted. Hinges are welded to the outer wall of the growth furnace body, and the hinges are connected to a furnace door via hinge shafts. The interior of the growth furnace body has a split-type thermal field structure, comprising a thermal field main body and wedge-shaped thermal field insulation components. By redesigning the structure of the growth furnace body, the top and bottom discharge method is changed to a side discharge method. A new design addresses the inconvenience of handling graphite crucibles, and the side-opening material handling operation ensures the relative position of the graphite crucible to the heating zone. The side-opening furnace door opening and closing mechanism effectively solves the problem of difficult cleaning in quartz induction and traditional resistance growth furnaces; it facilitates daily maintenance of the furnace body and effectively reduces growth quality problems caused by environmental contamination.

Description

TECHNICAL FIELD

[0001] The present application belongs to the technical field of single crystal growth equipment, and particularly relates to a side-opening resistance type silicon carbide single crystal growth furnace. BACKGROUND

[0002] In the actual silicon carbide growth process, each time the furnace is opened for loading and unloading operation, the hot field needs to be thoroughly cleaned. If the cleaning is not clean, the temperature will be directly affected by the dust, which cannot be accurately measured in the growth process, thereby causing the growth to fail. Secondly, the growth process will last for nearly 15 days, and the growth system cannot be opened during the process. Under the structure of the traditional growth furnace, all fasteners in the furnace body are checked and replaced only during annual maintenance and repair after assembly. Due to the inconvenience of operation, the fasteners will be missed, and the loosening caused by long-time operation will cause discharge phenomenon, which will affect the stable operation of the equipment. SUMMARY

[0003] Due to the deviation of the placement position of the traditional up-down loading and unloading crucible operation, the relative position of the crucible to the hot field changes, which causes poor consistency of the grown crystal. The side-opening growth furnace has the characteristics of side-opening loading and unloading, and the position of the crucible relative to the hot field is relatively accurate. By measuring the relative position, the accurate position of the crucible to the upper and lower heaters is ensured, which greatly improves the consistency of the grown crystal.

[0004] To solve the above problems, the present application discloses a side-opening resistance type silicon carbide single crystal growth furnace, which is realized by adopting a side-opening furnace body structure and a wedge-shaped heat preservation hot field structure. The temperature gradient of the powder zone and the seed zone is realized by controlling the structure and spacing of the graphite heater to realize the growth of silicon carbide single crystal.

[0005] To achieve the above purpose, the present application adopts the following technical scheme:

[0006] The side-opening resistance type silicon carbide single crystal growth furnace comprises a frame, a growth furnace body is installed on the frame, an articulated lug is welded on the outer side wall of the growth furnace body, and a furnace body door is connected to the articulated lug through an articulated shaft;

[0007] The inside of the growth furnace body has a split hot field structure, the split hot field structure comprises a hot field main body and a wedge-shaped hot field heat preservation component, the hot field main body is installed in the middle of the growth furnace body, wedge-shaped grooves are formed on both sides of the hot field main body, a graphite crucible is placed on the hot field main body, the hot field heat preservation component is fixed on the inner side of the furnace body door, and the hot field heat preservation component has wedge-shaped protrusions on both sides which cooperate with the wedge-shaped grooves;

[0008] A graphite heater is installed below the graphite crucible. The graphite heater is connected to a resistance heating power supply, a graphite heater and a controller. The controller is connected to a high-temperature infrared detector. The high-temperature infrared detector is used to detect the temperature of the graphite crucible and transmit the temperature signal to the controller. The controller controls the input power of the graphite heater through the resistance heating power supply.

[0009] Preferably, a quartz observation window is provided on the side of the growth furnace body, so that the closure status of the split thermal field structure can be observed through the quartz observation window after the furnace body door is closed.

[0010] Preferably, the graphite crucible has a heat-insulating shoulder in the middle and a heat-insulating partition at the bottom.

[0011] Preferably, the graphite heater comprises four heating units.

[0012] Preferably, graphite felt is adhered to both the wedge-shaped groove and the wedge-shaped protrusion.

[0013] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0014] 1. By redesigning the structure of the growth furnace, the top and bottom discharge method was changed to a side discharge method. A completely new design was implemented to address the inconvenience of handling graphite crucibles. The side-opening material handling operation ensures the relative position of the graphite crucible to the heating zone. The side-opening furnace door opening and closing mechanism effectively solves the problem of difficult cleaning inherent in quartz induction and traditional resistance growth furnaces; it facilitates daily furnace maintenance and effectively reduces growth quality problems caused by environmental contamination.

[0015] 2. To achieve the side-opening function requirement of the insulation, the split thermal field structure adopts a wedge-shaped structure design at the insulation splice. To ensure the long service life of the insulation components during the opening and closing process, graphite soft felt is used for flexible design on the splice section.

[0016] 3. In the low-temperature range below 1000 degrees Celsius, an open-loop constant power method is adopted. The controller writes the power value to the resistance heating power supply parameters through communication to realize the heating control of the system. In the high-temperature range of 1000 to 2500 degrees Celsius, the high-temperature infrared detector participates in the feedback closed-loop control of the system as a temperature sensor. The high-temperature infrared detector, resistance heating power supply, graphite heater and graphite crucible form a constant current closed-loop control system. Combined with power fuzzy control technology, the thermal field temperature control in the high-temperature range is realized. Attached Figure Description

[0017] The accompanying drawings, which form part of this application, are used to provide a further understanding of the invention. The illustrative embodiments of the invention and their descriptions are used to explain the invention and do not constitute an undue limitation of the invention. In the drawings:

[0018] Figure 1 This is a schematic diagram of the structure of the present invention;

[0019] Figure 2 This is a diagram showing the state of the furnace body when the door is open.

[0020] Figure 3 This is a schematic diagram of the main structure of the thermal field;

[0021] Figure 4 This is a schematic diagram of the thermal insulation component.

[0022] Figure 5 A schematic diagram showing the circuit connection of the graphite heater, the resistance heating power supply, the graphite heater, the controller, and the high-temperature infrared detector. Implementation

[0023] It should be noted that, unless otherwise specified, the embodiments and features described in this application can be combined with each other.

[0024] To enable those skilled in the art to better understand the present application, the technical solutions in the embodiments of the present application will be clearly and completely described below in conjunction with the embodiments of the present application. Obviously, the described embodiments are only some embodiments of the present application, and not all embodiments. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without creative effort should fall within the scope of protection of the present application.

[0025] like Figures 1-5 As shown, a side-opening resistance silicon carbide single crystal growth furnace includes a frame 1, on which a growth furnace body 2 is mounted. The outer side wall of the growth furnace body 2 is welded with a hinge lug 3, and the hinge lug 3 is connected to a furnace door 4 through a hinge shaft.

[0026] The interior of the growth furnace body 2 has a split-type thermal field structure, which includes a thermal field main body 5 and a wedge-shaped thermal field insulation component 6. The thermal field main body 5 is installed in the middle of the growth furnace body 2, and wedge-shaped grooves are respectively opened on both sides of the thermal field main body 5. A graphite crucible 7 is placed on the thermal field main body 5. The thermal field insulation component 6 is fixed to the inner side of the furnace door 4, and wedge-shaped protrusions that cooperate with the wedge-shaped grooves are respectively on both sides of the thermal field insulation component 6.

[0027] A graphite heater 8 is installed below the graphite crucible 7. The graphite heater 8 is connected to a resistance heating power supply 9, a controller 10, and a high-temperature infrared detector 11. The high-temperature infrared detector 11 is used to detect the temperature of the graphite crucible 7 and transmit the temperature signal to the controller 10. The controller 10 controls the input power of the graphite heater 8 through the resistance heating power supply 9.

[0028] A quartz observation window 12 is provided on the side of the growth furnace body 2, so that the closure status of the split thermal field structure can be observed through the quartz observation window 12 after the furnace door 4 is closed.

[0029] The graphite crucible 7 has a heat-insulating shoulder in the middle and a heat-insulating partition at the bottom.

[0030] The graphite heater 8 includes four heating units, and the heater is connected for heating and conduction by designing conductive contacts.

[0031] Both the wedge-shaped groove and the wedge-shaped protrusion are bonded with graphite soft felt, and the flexible design ensures the long service life of the split thermal field structure during the opening and closing of the insulation process.

[0032] The above description is merely a preferred embodiment of the present invention and is not intended to limit the invention. Various modifications and variations can be made to the present invention by those skilled in the art. Any modifications, equivalent substitutions, improvements, component splitting or combination, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A side-seal resistance type silicon carbide single crystal growth furnace, characterized by comprising: The frame is provided with a growth furnace body, the growth furnace body is provided with a hinge ear welded on the outer side wall, and the hinge ear is connected with a furnace body door through a hinge shaft; The growth furnace body is internally provided with a split heat field structure, the split heat field structure comprises a heat field main body and a wedge-shaped heat field insulation component, the heat field main body is arranged in the middle of the growth furnace body, wedge-shaped grooves are arranged on both sides of the heat field main body, a graphite crucible is arranged on the heat field main body, the heat field insulation component is fixed on the inner side of the furnace body door, and the heat field insulation component is provided with wedge-shaped protrusions on both sides and matched with the wedge-shaped grooves; The graphite heater is connected with a resistance heating power supply, a graphite heater and a controller, the controller is connected with a high-temperature infrared detector, the high-temperature infrared detector is used for detecting the temperature of the graphite crucible and transmitting a temperature signal to the controller, and the controller controls the input power of the graphite heater through the resistance heating power supply; In the low-temperature section below 1000 DEG C, an open-loop constant power mode is adopted, the controller writes a power value into the resistance heating power supply through communication, and the heating control of the system is realized; in the high-temperature section of 1000 DEG C to 2500 DEG C, the high-temperature infrared detector is used as a temperature sensor to participate in the feedback closed-loop control of the system, the high-temperature infrared detector, the resistance heating power supply, the graphite heater and the graphite crucible form a constant current closed-loop control system, and the power fuzzy control technology is combined to realize the heat field temperature control in the high-temperature section.

2. The lateral resistance SiC single crystal growth furnace of claim 1, wherein The side surface of the growth furnace body is provided with a quartz observation window, and the closed state of the split heat field structure is observed through the quartz observation window after the furnace body door is closed.

3. The lateral resistance SiC single crystal growth furnace of claim 1, wherein The middle part of the graphite crucible is provided with an insulation shoulder, and the bottom of the graphite crucible is provided with an insulation partition plate.

4. The lateral resistance SiC single crystal growth furnace of claim 1, wherein The graphite heater comprises four heating units.

5. The lateral resistance SiC single crystal growth furnace of claim 1, wherein The wedge-shaped grooves and the wedge-shaped protrusions are all bonded with graphite soft felt.

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