Material preparation assembly and crystal growth equipment

Abstract

The embodiment of the invention provides a material preparation assembly and crystal growth equipment. The material preparation assembly comprises a tunnel furnace and a plurality of raw material furnaces, the tunnel furnace comprises a heating chamber and a motion driving mechanism, the plurality of raw material furnaces are sequentially arranged in the heating chamber along the length direction of the tunnel furnace, and the motion driving mechanism drives the plurality of raw material furnaces to move along the length direction of the tunnel furnace; and a material heating mechanism is arranged in the heating chamber and is used for heating the raw material furnace.

Description

Technical Field

[0001] The present invention relates to the field of crystal growth, and in particular to a material preparation component and a crystal growth device. Background Art

[0002] In many industrial productions, material preparation is required. For example, for the production of semiconductor crystals using the physical vapor transport (PVT) method, it is necessary to prepare materials for crystal growth. How to improve the efficiency of material preparation is a technical problem that needs to be solved urgently in this field. Summary of the invention

[0003] One of the embodiments of the present specification provides a material preparation component, which includes a tunnel furnace and multiple raw material furnaces; the tunnel furnace includes a heating chamber and a motion drive mechanism, the multiple raw material furnaces are arranged in the heating chamber in sequence along the length direction of the tunnel furnace, and the motion drive mechanism drives the multiple raw material furnaces to move along the length direction of the tunnel furnace; a material heating mechanism is provided in the heating chamber, and the material heating mechanism is used to heat the raw material furnace.

[0004] In some embodiments, the tunnel furnace further includes a heat-insulating layer, which insulates the heating chamber; and / or the tunnel furnace further includes a cooling mechanism, which is disposed outside the heating chamber.

[0005] In some embodiments, the heating chamber includes a preheating section, a heating section and a cooling section separated from each other in sequence along the length direction of the tunnel furnace; the maximum temperature in the heating section is higher than the maximum temperature in the preheating section and the maximum temperature in the cooling section; each of the preheating section, the heating section and the cooling section is provided with a first temperature measuring mechanism and a first pressure measuring mechanism.

[0006] In some embodiments, the tunnel furnace includes a temperature measuring component, which can measure the temperature in each of the raw material furnaces.

[0007] In some embodiments, the temperature measuring component includes an electric rail and multiple thermometers, and the multiple thermometers respectively measure the temperatures in multiple raw material furnaces. The electric rail is arranged on the outside of the raw material furnace, and the part of each of the multiple thermometers that passes through the raw material furnace is in sliding electrical contact with the electric rail, and the electric rail is parallel to the length direction of the tunnel furnace.

[0008] In some embodiments, the multiple raw material furnaces are connected in sequence, and the motion driving mechanism includes a push rod or a pull rod, and the push rod or the pull rod is connected to one of the multiple raw material furnaces.

[0009] In some embodiments, the device further comprises at least one of a mixing chamber, a compacting chamber, and a pre-vacuum chamber; the mixing chamber comprises a pressure relief device and / or a weighing device.

[0010] In some embodiments, the raw material furnace includes a raw material furnace body and an upper cover, and the upper cover is provided with a seed crystal bonding surface.

[0011] In some embodiments, there are multiple material heating mechanisms, and the multiple material heating mechanisms are respectively arranged around the multiple raw material furnaces, and each of the raw material furnaces is provided with a second temperature measuring mechanism and a second pressure measuring mechanism.

[0012] The embodiments of the present specification also provide a crystal growth device, which includes a furnace body, a crucible, a heating component and a material preparation component described in any of the above technical solutions; wherein the furnace body includes a furnace chamber, the crucible and the heating component are both arranged in the furnace chamber; the heating component heats the crucible; and the material preparation component prepares material placed in the crucible for crystal growth. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] This specification will be further described in the form of exemplary embodiments, which will be described in detail by the accompanying drawings. These embodiments are not restrictive, and in these embodiments, the same number represents the same structure, wherein:

[0014] Figure 1 is a schematic diagram of the structure of a material preparation assembly according to some embodiments of this specification;

[0015] Figure 2 is a schematic diagram of the structure of a raw material furnace according to some embodiments of this specification;

[0016] Figure 3 is a block diagram of a crystal growth apparatus according to some embodiments of the present specification;

[0017] Figure 4 It is a schematic diagram of the structure of the crystal growth equipment shown in some embodiments of this specification.

[0018] Explanation of the reference numerals: 100, crystal growth equipment; 110, furnace body; 120, crucible; 130, heating assembly; 140, material; 121, upper cover; 122, main body; 190, material preparation assembly; 191, tunnel furnace; 1911, heating chamber; 19111, preheating section; 19112, heating section; 19113, cooling section; 1912, motion drive mechanism; 19121, push rod; 1913, insulation layer; 1914, compacting chamber; 1915, pre-vacuum chamber; 1916, mixing chamber; 192, raw material furnace; 1921, raw material furnace body; 1922, upper cover; 1923, seed crystal bonding surface; 1924, material heating mechanism; 200, seed crystal. DETAILED DESCRIPTION

[0019] In order to more clearly illustrate the technical solutions of the embodiments of this specification, the following is a brief introduction to the drawings required for the description of the embodiments. Obviously, the drawings described below are only some examples or embodiments of this specification. For ordinary technicians in this field, this specification can also be applied to other similar scenarios based on these drawings without creative work. Unless it is obvious from the language environment or otherwise explained, the same reference numerals in the figures represent the same structure or operation.

[0020] As shown in this specification and claims, unless the context clearly indicates an exception, the words "a", "an", "an" and / or "the" do not refer to the singular and may also include the plural, unless the context clearly indicates an exception. Generally speaking, the terms "include" and "comprise" only indicate the inclusion of the steps and elements that have been clearly identified, and these steps and elements do not constitute an exclusive list. The method or device may also include other steps or elements. The term "based on" means "at least partially based on". The term "one embodiment" means "at least one embodiment"; the term "another embodiment" means "at least one other embodiment".

[0021] In this specification, unless otherwise clearly specified and limited, the terms "installed", "connected", "connected", "fixed" and the like should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; 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 the internal connection of two elements or the interaction relationship between two elements, unless otherwise clearly defined. For ordinary technicians in this field, the specific meanings of the above terms in this specification can be understood according to specific circumstances.

[0022] It should be understood that the "system", "device", "unit" and / or "module" used herein are a method for distinguishing different components, elements, parts, portions or assemblies at different levels. However, if other words can achieve the same purpose, the words can be replaced by other expressions.

[0023] Unless otherwise indicated, the words "top", "bottom", "side", "lower" and / or "upper" and the like are for convenience of description only and are not limited to a position or a spatial orientation. Generally speaking, the terms "include" and "comprise" only indicate the inclusion of the steps and elements that have been clearly identified, and these steps and elements do not constitute an exclusive list, and the method or device may also include other steps or elements.

[0024] The embodiments of this specification provide a material preparation component. Figure 1 Schematic diagram of the structure of the material preparation assembly according to some embodiments of this specification. Figure 1 As shown, the crystal growth equipment 100 also includes a material preparation component 190, and the material preparation component 190 includes a tunnel furnace 191 and a plurality of raw material furnaces 192. The tunnel furnace 191 includes a heating chamber 1911 and a motion drive mechanism 1912. The plurality of raw material furnaces 192 are sequentially arranged in the heating chamber 1911 along the length direction of the tunnel furnace 191. The motion drive mechanism 1912 drives the plurality of raw material furnaces 192 to move along the length direction of the tunnel furnace 191. A material heating mechanism 1924 is arranged in the heating chamber 1911, and the material heating mechanism 1924 is used to heat the raw material furnace 192.

[0025] In some embodiments, the material is a raw material for growing a crystal. The raw material may include a material for supplying a seed crystal to grow into a crystal. In some embodiments, the component of the raw material of the silicon carbide crystal may include SiC. In some embodiments, the component of the raw material of the aluminum nitride crystal may include AlN. In some embodiments, the raw material may be a powder, granular and / or bulk material.

[0026] The tunnel furnace 191 refers to a device that centrally sets up the material preparation process. The tunnel furnace 191 can be understood as a furnace body that provides a cavity with a longer length, and in the cavity, an object can move along the direction of the longer length (hereinafter referred to as the length direction of the tunnel furnace 191). A heating chamber 1911 can be formed in the cavity of the tunnel furnace 191. The material heating mechanism 1924 is used to heat the raw material furnace 192 in the heating chamber 1911. The material heating mechanism 1924 can heat the raw material furnace 192 in the heating chamber to provide the raw material furnace 192 with the temperature required for material preparation. The raw material furnace 192 is used to provide a place for material generation. In some embodiments, the raw material furnace 192 includes a raw material furnace body 1921 and an upper cover 1922, and the raw material furnace 192 body 1921 forms a containing cavity to accommodate materials for preparing raw materials. In some embodiments, the raw materials for preparing materials may include carbon powder and silicon powder. Carbon powder and silicon powder are mixed in the raw material furnace 192 to prepare silicon carbide materials.

[0027] In some embodiments, a plurality of raw material furnaces 192 are arranged along the length direction of the tunnel furnace 191 (see Figure 1 ) are sequentially arranged in the heating chamber 1911. The motion drive mechanism 1912 can drive multiple raw material furnaces 192 to move along the length direction of the tunnel furnace 191. The motion drive mechanism 1912 can realize the transportation of the raw material furnace 192 in the tunnel furnace 191. Through the arrangement of the heating chamber 1911, the material heating mechanism 1924 and the motion drive mechanism 1912, the raw material furnace 192 can be heated in the tunnel furnace 191. The material heating mechanism 1924 can control the temperature of the heating chamber, and cooperate with the motion drive mechanism 1912 to control the transportation speed and residence time of the raw material furnace 192 in the tunnel furnace 191, thereby controlling the temperature and time of the raw material furnace 192 being heated, thereby accurately realizing the preparation of the material. And because a tunnel furnace 191 is arranged, multiple raw material furnaces 192 can be heated at the same time and sequentially transported out of the tunnel furnace 191. In addition, the prepared materials in the raw material furnace 192 can be taken out and raw materials can be put into the raw material furnace 192 again, and the raw material furnace 192 can be sent into the tunnel furnace 191 again in a cycle to realize the circular preparation of materials, which greatly improves the efficiency of material preparation.

[0028] In some embodiments, the motion driving mechanism 1912 includes a conveyor mechanism, which is arranged along the length direction of the tunnel furnace 191, and the raw material furnace 192 is placed on the conveyor mechanism, and the conveyor mechanism drives the multiple raw material furnaces 192 to move along the length direction of the tunnel furnace 191. In some embodiments, the multiple raw material furnaces 192 are connected in sequence, and the motion driving mechanism 1912 includes a push rod 19121 or a pull rod, and the push rod 19121 or the pull rod is connected to one of the multiple raw material furnaces 192. The push rod 19121 pushes or the pull rod pulls one of the multiple raw material furnaces 192, so that the multiple raw material furnaces 192 can be driven to move together. In some embodiments, the push rod 19121 or the pull rod is arranged on one side of the multiple raw material furnaces 192 as a whole, and the push rod 19121 or the pull rod is connected to the raw material furnace 192 closest to it. The motion driving mechanism 1912 uses a push rod 19121 or a pull rod, which has a simple structure, can withstand the high temperature in the heating chamber 1911, and has a reduced failure rate.

[0029] In some embodiments, in order to reduce the heat dissipation in the heating chamber 1911, the tunnel furnace 191 further includes an insulation layer 1913, and the insulation layer 1913 insulates the heating chamber 1911. The insulation layer 1913 can be arranged inside the heating chamber 1911 (such as attached to the inner wall of the heating chamber 1911), or can be arranged outside the heating chamber 1911 (such as wrapped outside the tunnel furnace 191). The insulation layer 1913 can include insulation felt, insulation coating, etc. For example, the insulation layer 1913 can be an insulation coating coated on the inner wall of the heating chamber 1911 (which can include the top wall, the bottom wall and the side wall). For another example, the insulation layer 1913 can be an insulation felt wrapped outside the tunnel furnace 191 at the position corresponding to the heating chamber 1911.

[0030] In some embodiments, the heating chamber 1911 includes a preheating section 19111, a heating section 19112 and a cooling section 19113 in sequence along the length direction of the tunnel furnace 191, and the preheating section 19111, the heating section 19112 and the cooling section 19113 are separated from each other. The highest temperature in the heating section 19112 is higher than the highest temperature in the preheating section 19111, and the highest temperature in the heating section 19112 is higher than the highest temperature in the cooling section 19113. In other words, the tunnel furnace 191 is divided into at least three sections along the length direction, and the heating temperature of the raw material furnace 192 in the at least three sections may be different. During the material preparation process, the heating of the raw materials in the raw material furnace 192 will go through three stages, namely the preheating stage, the heating stage and the cooling stage.

[0031] In the preheating stage, since the raw material furnace 192 is placed in the heating chamber 1911, the temperature in the raw material furnace 192 is continuously or periodically increased from room temperature to reach or approach (below) the first preset temperature. In some embodiments, the first preset temperature may be 2000°C-2200°C. In the heating stage, the temperature in the raw material furnace 192 is further increased, and after reaching the second preset temperature, it begins to be kept warm. In some embodiments, the second preset temperature may be 2050°C-2300°C. In the cooling stage, the temperature in the raw material furnace 192 begins to decrease continuously or periodically.

[0032] In some embodiments, the temperature of the preheating section 19111 is room temperature-2000°C, and the temperature of the heating section 19112 can be 2000°C-2300°C. In some embodiments, the residence time of the raw material furnace 192 in the preheating section 19111 can be 5-10 hours. In some embodiments, the residence time of the raw material furnace 192 in the heating section 19112 can be 10-50 hours. In some embodiments, the temperature of the cooling section 19113 is 2300-800°C, and the residence time of the raw material furnace 192 in the cooling section 19113 can be 20 hours-50 hours.

[0033] The motion drive mechanism 1912 can transport multiple raw material furnaces 192 according to a preset time to control the residence time of the raw material furnace 192 in each section (preheating section 19111, heating section 19112 and cooling section 19113) to achieve temperature control during the material preparation process. Through such a setting, material preparation can be cyclically performed in multiple raw material furnaces 192, thereby improving the material preparation efficiency.

[0034] In some embodiments, the material heating mechanism 1924 can be arranged in the preheating section 19111 and the heating section 19112 of the heating chamber 1911, and the material heating mechanism 1924 is used to heat the raw material furnace 192 of the preheating section 19111 and the heating section 19112. It should be noted that the preheating of the preheating section 19111 and the heating of the heating section 19112 are only for the preparation stage of the raw materials, and do not represent the limitation of the temperature of the preheating section 19111 and the heating section 19112. In other words, the temperature of the preheating section 19111 can be higher than, equal to or lower than the temperature of the heating section 19112, and the temperature of the preheating section 19111 and the heating section 19112 can be set based on the preparation requirements of the raw materials. In other embodiments, the material heating mechanism 1924 can include a first heating component, which can be arranged in the preheating section 19111 and the heating section 19112, and the first heating component can heat the preheating section 19111 and the heating section 19112 together. At this time, through the setting position of the first heating component, in some embodiments, the material heating mechanism 1924 may include a second heating component and a third heating component, the second heating component may be arranged in the preheating section 19111, and the third heating component may be arranged in the heating section 19112. In this way, the temperature of the preheating section 19111 and the heating section 19112 can be controlled more flexibly. In some embodiments, the material heating mechanism 1924 may also include a heating component, and the heating component may be arranged in the cooling section. By controlling the heating temperature of the cooling section by the heating component, the cooling rate of the material synthesized in the raw material furnace can be controlled. In some embodiments, the residence time of each raw material furnace 192 in the preheating section 19111 and the heating section 19112 can be controlled by the motion drive mechanism 1912, and then in coordination with the heating temperature of the material heating mechanism 1924, the heat obtained by each raw material furnace can be controlled, thereby meeting the needs of material preparation.

[0035] In some embodiments, a plurality of pressure control mechanisms may be provided in the tunnel furnace 191 to respectively control the pressures of the preheating section 19111, the heating section 19112, and the cooling section 19113. In some embodiments, the pressure control mechanism may include a butterfly valve, a mechanical pump, and the like.

[0036] In some embodiments, each of the preheating section 19111, the heating section 19112, and the cooling section 19113 is provided with a first temperature measuring mechanism and a first pressure measuring mechanism, and the temperature and pressure of the preheating section 19111, the heating section 19112, and the cooling section 19113 are measured respectively, so as to control the temperature and pressure in each area separately. That is, the tunnel furnace 191 may include multiple first temperature measuring mechanisms and multiple first pressure measuring mechanisms. Multiple first temperature measuring mechanisms are arranged at positions corresponding to different sections (preheating section 19111, heating section 19112, and cooling section 19113) in the heating chamber 1911, and multiple first pressure measuring mechanisms are arranged at positions corresponding to different sections (preheating section 19111, heating section 19112, and cooling section 19113) in the heating chamber 1911. In some embodiments, the first temperature measuring mechanism may include an infrared thermometer.

[0037] In some embodiments, the tunnel furnace 191 includes a temperature measuring component that can measure the temperature in multiple raw material furnaces 192. Through such a setting, the operator can know the temperature in each raw material furnace, which is conducive to the operator's understanding of the temperature conditions in each raw material furnace 192 during the raw material production process.

[0038] In some embodiments, the temperature measurement assembly includes an electric rail and a plurality of thermometers. The plurality of thermometers respectively measure the temperature in the plurality of raw material furnaces 192 by extending into the raw material furnace 192. The electric rail is arranged outside the raw material furnace 192, and the portion of each of the plurality of thermometers that passes through the raw material furnace 192 is in sliding electrical contact with the electric rail. The electric rail is parallel to the length direction of the tunnel furnace 191. In some embodiments, the electric rail is located in the heating chamber 1911 to prevent the thermometer from passing through the heating chamber 1911 and destroying the temperature field in the heating chamber. Specifically, the thermometer keeps measuring the temperature in the raw material furnace 192 and keeps in sliding electrical contact with the electric rail. When the raw material furnace 192 moves under the drive of the motion drive mechanism 1912, the thermometer in the raw material furnace 192 also moves accordingly. The thermometer slides relative to the electric rail, and the temperature is monitored during the movement of the raw material furnace 192.

[0039] The thermometer is in sliding electrical contact with the electric rail, so that the electric rail can supply power to the thermometer in real time. In some embodiments, the temperature signal detected by the thermometer can be derived through the electric rail. Through such a setting, the thermometer can continuously measure the temperature during the transportation of the raw material furnace 192, and the measured temperature can also be conveniently transmitted. In some embodiments, a temperature measuring port can be provided on the raw material furnace, and the thermometer is fixed at the temperature measuring port for temperature measurement. The electric rail is located at the upper part of the raw material furnace in the axial direction. Specifically, the thermometer is kept in the temperature measuring port, and the part passing through the temperature measuring port is kept in sliding electrical contact with the electric rail. When the raw material furnace is transported by the motion drive mechanism 1912, the thermometer slides relative to the electric rail, and the temperature is monitored during the movement of the raw material furnace 192. In other embodiments, the thermometer can be fixed to the side wall of the raw material furnace 192 to measure the temperature of the material in the crucible 120 of the raw material furnace 192. In some embodiments, a sealing structure can be provided at the position where the thermometer passes through the side wall or bottom wall of the raw material furnace 192.

[0040] In some embodiments, the tunnel furnace 191 also includes a cooling mechanism, which is arranged outside the heating chamber 1911. The cooling mechanism can cool down the entire heating furnace by water cooling, air cooling, etc. As an example only, a water cooling pipe can be coiled on the furnace wall of the tunnel furnace 191. The cooling mechanism is used to prevent the temperature of the tunnel furnace 191 from being too high during the heating process, which may cause danger. In some embodiments, due to the high temperatures of the preheating section 19111 and the heating section 19112, the furnace body portion of the tunnel furnace 191 corresponding to the preheating section 19111 and the heating section 19112 is provided with a cooling mechanism. In some embodiments, the cooling mechanism includes a double-layer water-cooling structure, the water inlet of the water-cooling structure is equipped with a water flow sensor, and the water outlet is equipped with a water temperature sensor, which monitors the water flow and temperature of the cooling water in real time to ensure safety.

[0041] In some embodiments, the tunnel furnace 191 further includes a mixing chamber 1916, a compacting chamber 1914, and a pre-vacuum chamber 1915. The mixing chamber 1916 is used to mix raw materials (such as carbon powder and silicon powder); the compacting chamber 1914 is used to compact the raw materials; and the pre-vacuum chamber 1915 is used to extract the air in the raw material furnace 192. In some embodiments, the mixing chamber 1916 includes a mixing barrel and a rotating device. The mixing chamber 1916 rotates the mixing barrel as a whole to mix the materials in the mixing barrel. In some embodiments, the compacting chamber 1914 uses hydraulic technology (such as a hydraulic hammer) or other means to compact the materials. In some embodiments, the pre-vacuum chamber 1915 is provided with a vacuum gauge, which can monitor the vacuum degree and pressure in the raw material furnace 192 in real time. By pre-vacuuming the raw material furnace 192, the risk of explosion caused by heating the raw materials in subsequent steps can be avoided. In some embodiments, the mixing chamber 1916 also includes a pressure relief device. Since the raw materials (such as carbon powder and silicon powder) will form high pressure in the mixing chamber after high-speed rotation in the mixing chamber, the pressure relief device is used to restore the air pressure in the mixing chamber 1916 to atmospheric pressure to ensure safety during the production process. In some embodiments, the mixing chamber includes a weighing device. The weighing device can more conveniently determine the weight of various raw materials to ensure the accurate proportion of various raw materials.

[0042] Figure 2 1 is a schematic diagram of a raw material furnace according to some embodiments of the present specification. In some embodiments, the raw material furnace 192 can be used to produce bulk materials. Figure 2 As shown, the raw material furnace 192 may include a raw material furnace body 1921 and an upper cover 1922, and the upper cover 1922 is provided with a seed crystal bonding surface 1923, and a seed crystal is bonded to the seed crystal bonding surface 1923. The raw material for producing the material is placed at the bottom of the raw material furnace 192, and the temperature field distribution in the raw material furnace 192 is controlled so that the material is continuously sublimated and consumed, and then a crystal material is grown on the seed crystal. Specifically, by controlling the temperature field distribution in the raw material furnace 192, an axial temperature gradient is formed between the raw material and the seed crystal on the seed crystal bonding surface 1923. The material placed at the bottom of the raw material furnace 192 is sublimated into a gas phase component under high temperature conditions, and the gas phase component is transmitted to the seed crystal in the low temperature zone under the drive of the axial temperature gradient. Since the temperature at the position of the seed crystal is relatively low, the gas phase component can generate a crystal material on the surface of the seed crystal. The crystal material can be formed into a block after being crushed, and the block can be used as a raw material for growing crystals by physical vapor transport (PVT).

[0043] In some embodiments, the seed crystal bonding surface 1923 may be made of graphite. In some embodiments, the seed crystal bonding surface 1923 is the inner side of the upper cover 1922, and the seed crystal may be fixedly bonded to the seed crystal bonding surface 1923. In some embodiments, the seed crystal 200 may be fixed to the seed crystal bonding surface 1923 by an adhesive. The adhesive may include, but is not limited to, epoxy resin glue, AB glue, phenolic resin glue, sugar glue, etc.

[0044] In some embodiments, the material heating mechanism 1924 is disposed outside the raw material furnace 192 to heat the raw material furnace 192. In some embodiments, the material heating mechanism 1924 can heat the side of the raw material furnace 192. For example, the material heating mechanism 1924 is a heating pipe disposed around the side of the raw material furnace 192. In some embodiments, the number of the material heating mechanism 1924 is multiple, and the multiple material heating mechanisms 1924 are disposed around the multiple raw material furnaces 192 respectively. In this way, the temperature in each raw material furnace 192 can be more accurately controlled, and the heating effect is better. In some embodiments, the material heating mechanism 1924 can be disposed at the bottom of the raw material furnace 192. In this way, a larger axial temperature gradient can be formed in the raw material furnace 192, which is conducive to the transmission of the sublimated raw materials. For example, the material heating mechanism 1924 can be a resistance heater disposed at the bottom of the raw material furnace 192. In some embodiments, each raw material furnace 192 is provided with a second temperature measuring mechanism and a second pressure measuring mechanism, and each raw material furnace 192 is individually measured in temperature and pressure, so as to individually control the temperature and pressure in each raw material furnace 192. Since each raw material furnace 192 is provided with a corresponding material heating mechanism 1924 , the conditions in each raw material furnace 192 may be different. The second temperature measuring mechanism and the second pressure measuring mechanism can better detect the temperature and pressure in each raw material furnace 192 .

[0045] The present specification also provides a crystal growth device. Figure 3 FIG. 1 is a block diagram of a crystal growth device according to some embodiments of the present specification. Figure 3 As shown, the crystal growth device 100 includes a furnace body 110, a crucible 120, a heating assembly 130 and a material preparation assembly 190 described in any of the above technical solutions. The heating assembly 130 heats the crucible 120. The material preparation assembly 190 is used to provide the crucible 120 with materials.

[0046] The crystal growth apparatus 100 can be used to prepare a crystal. In some embodiments, the crystal growth apparatus 100 can prepare a crystal based on a physical vapor transport (PVT) method. In some embodiments, the crystal can include but is not limited to a silicon carbide crystal, an aluminum nitride crystal, a zinc oxide crystal, or a zinc antimonide crystal.

[0047] The furnace body 110 is a structure for accommodating the crucible 120 and the heating assembly 130. In some embodiments, the furnace body 110 includes a furnace, and the crucible 120 and the heating assembly 130 are both arranged in the furnace. The crucible 120 is used to provide a place for crystal growth. In some embodiments, the crucible 120 includes an inner cavity and a wall body surrounding the inner cavity, and the material 140 is accommodated in the inner cavity of the crucible 120. In some embodiments, the material prepared by the material preparation assembly 190 can be placed in the inner cavity of the crucible 120 by manual placement, equipment transportation, etc.

[0048] In some embodiments, the crucible 120 may include an upper cover 121 and a main body 122. The main body 122 may include the wall body surrounding the inner cavity as described above, and the inner cavity is formed in the main body 122. The upper cover 121 may be located on the top of the main body 122 to close the top opening of the main body 122.

[0049] In some embodiments, a seed crystal 200 is provided above the crucible 120, and a material 140 is provided inside the crucible 120. In some embodiments, the seed crystal 200 can be bonded to the upper cover 121. The seed crystal 200 can be a small crystal having the same crystal orientation as the crystal to be grown, and can be used as a seed for growing a crystal. In some embodiments, the seed crystal 200 can be made based on a physical vapor transport (PVT) method, a chemical vapor deposition (CVD) method, or a pulling method. In some embodiments, the size of the seed crystal 200 can be 4 inches, 8 inches, etc. The type of the seed crystal 200 can be a 4H-SiC seed crystal, a 6H-SiC seed crystal, etc.

[0050] like Figure 4 As shown, the seed crystal 200 can be bonded to the lower side of the upper cover 121 , and the material 140 can be placed in the main body 122 . Figure 4 The middle dotted line a shows the lower surface of the seed crystal 200. Figure 4 The dotted line b shows the upper surface of the material 140, and the space between the dotted line a and the dotted line b is the space for crystal growth.

[0051] In the crystal growth stage, the material 140 in the crucible 120 is heated and sublimated into gas phase components, which are transported to the seed crystal 200 in the crystallization region and then crystallized on the surface of the seed crystal 200 to generate crystals.

[0052] The heating assembly 130 is used to heat the crucible 120 to provide a temperature field required for crystal growth. In some embodiments, when the heating assembly 130 heats the crucible 120, a temperature field can be formed inside the crucible 120 (i.e., in the inner cavity) to heat the material 140, so that the material 140 sublimates and grows a crystal on the growth surface of the seed crystal 200.

[0053] In some embodiments, the heating assembly 130 may include, but is not limited to, an electromagnetic induction heater, a resistance heater, etc. In some embodiments, the electromagnetic induction heater may include an induction coil. Under the action of alternating currents of different frequencies, the induction coil may generate eddy currents on the outer wall of the crucible 120. Under the action of the eddy currents, the electrical energy generated on the outer wall of the crucible 120 may be converted into thermal energy, and the thermal energy is conducted from the wall of the crucible 120 to the inside of the crucible 120 to form a temperature field inside the crucible 120.

[0054] In some embodiments, when the heating component 130 is an electromagnetic induction heater, the electromagnetic induction heater can be arranged around the crucible 120. In some embodiments, the electromagnetic induction heater can be disposed in an outer region of the crucible 120 at a certain distance from the outer wall of the crucible 120. In some embodiments, when the heating component 130 is a resistance heater, the resistance heater can be disposed on the crucible wall (such as the bottom wall or the side wall) of the crucible 120. For example, embedded in the crucible wall of the crucible 120, or connected to the outer surface of the crucible wall of the crucible 120. In other embodiments, when the heating component 130 is a resistance heater, the resistance heater can be disposed at a certain distance from the crucible wall (such as the bottom wall or the side wall) of the crucible 120.

[0055] The heating of the crucible 120 by the heating assembly 130 will form a temperature gradient in the crucible 120 (in the inner cavity). The temperature gradient may include an axial temperature gradient and a radial temperature gradient. The axial temperature gradient refers to the temperature difference per unit distance in the direction of the central axis of the inner cavity of the crucible 120. During the crystal growth process, the temperature decreases from the bottom of the inner cavity to the top in the direction of the central axis of the inner cavity to form an axial temperature gradient, and such an axial temperature gradient can drive the gas phase components of the sublimated material 140 to be transferred to the crystal growth surface. The radial temperature gradient refers to the temperature difference per unit distance in the direction from the inner wall of the crucible 120 to the central axis of the crucible 120 on a horizontal cross section at the same height of the inner cavity. During the crystal growth process, since the heating assembly 130 generally heats the crucible 120 from the outside of the crucible 120, a radial temperature gradient with decreasing temperature will be presented in the direction from the inner wall of the crucible 120 to the central axis of the crucible 120.

[0056] It should be noted that different embodiments may produce different beneficial effects. In different embodiments, the beneficial effects that may be produced may be any one or a combination of the above, or any other beneficial effects that may be obtained.

[0057] Finally, it should be understood that the embodiments described in this application are only used to illustrate the principles of the embodiments of the present application. Other variations may also fall within the scope of the present application. Therefore, as an example and not a limitation, the alternative configurations of the embodiments of the present application may be considered to be consistent with the teachings of the present application. Accordingly, the embodiments of the present application are not limited to the embodiments explicitly introduced and described in the present application.

Claims

1. A material preparation component, characterized in that: The material preparation assembly includes a tunnel furnace and a plurality of raw material furnaces; The tunnel furnace comprises a heating chamber and a motion driving mechanism, the multiple raw material furnaces are sequentially arranged in the heating chamber along the length direction of the tunnel furnace, and the motion driving mechanism drives the multiple raw material furnaces to move along the length direction of the tunnel furnace; A material heating mechanism is provided in the heating chamber, and the material heating mechanism is used to heat the raw material furnace.

2. The material preparation assembly according to claim 1, characterized in that: The tunnel furnace further comprises a heat-insulating layer, and the heat-insulating layer keeps the heating chamber warm; and / or, The tunnel furnace further comprises a cooling mechanism, which is arranged outside the heating chamber.

3. The material preparation assembly according to claim 1, characterized in that: The heating chamber includes a preheating section, a heating section and a cooling section which are separated from each other in sequence along the length direction of the tunnel furnace; the highest temperature in the heating section is higher than the highest temperature in the preheating section and the highest temperature in the cooling section; Each of the preheating section, the heating section and the cooling section is provided with a first temperature measuring mechanism and a first pressure measuring mechanism.

4. The material preparation assembly according to claim 1, characterized in that: The tunnel furnace comprises a temperature measuring component, and the temperature measuring component can measure the temperature in each of the raw material furnaces.

5. The material preparation assembly according to claim 4, characterized in that: The temperature measuring component includes an electric rail and multiple thermometers, which respectively measure the temperatures in multiple raw material furnaces. The electric rail is arranged outside the raw material furnace, and the part of each of the multiple thermometers that passes through the raw material furnace is in sliding electrical contact with the electric rail. The electric rail is parallel to the length direction of the tunnel furnace.

6. The material preparation assembly according to claim 1, characterized in that: The multiple raw material furnaces are connected in sequence, and the motion driving mechanism includes a push rod or a pull rod, and the push rod or the pull rod is connected to one of the multiple raw material furnaces.

7. The material preparation assembly according to claim 1, characterized in that: The equipment further comprises at least one of a mixing chamber, a compacting chamber and a pre-vacuum chamber; the mixing chamber comprises a pressure relief device and / or a weighing device.

8. The material preparation assembly according to claim 1, characterized in that: The raw material furnace comprises a raw material furnace body and an upper cover, and the upper cover is provided with a seed crystal bonding surface.

9. The material preparation assembly according to claim 8, characterized in that: There are multiple material heating mechanisms, and the multiple material heating mechanisms are respectively arranged around the multiple raw material furnaces. Each of the raw material furnaces is provided with a second temperature measuring mechanism and a second pressure measuring mechanism.

10. A crystal growth device, characterized in that: The device includes a furnace body, a crucible, a heating component and a material preparation component according to any one of claims 1 to 9; wherein the furnace body includes a furnace chamber, the crucible and the heating component are both arranged in the furnace chamber; the heating component heats the crucible; and the material preparation component prepares material placed in the crucible for crystal growth.

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