CN115029781A - Method and device for growing silicon carbide single crystal by liquid phase method - Google Patents
Method and device for growing silicon carbide single crystal by liquid phase method Download PDFInfo
- Publication number
- CN115029781A CN115029781A CN202210903128.3A CN202210903128A CN115029781A CN 115029781 A CN115029781 A CN 115029781A CN 202210903128 A CN202210903128 A CN 202210903128A CN 115029781 A CN115029781 A CN 115029781A
- Authority
- CN
- China
- Prior art keywords
- seed crystal
- raw material
- growth
- growing
- growth raw
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Pending
Links
Images
Classifications
-
- C—CHEMISTRY; METALLURGY
- C30—CRYSTAL GROWTH
- C30B—SINGLE-CRYSTAL GROWTH; UNIDIRECTIONAL SOLIDIFICATION OF EUTECTIC MATERIAL OR UNIDIRECTIONAL DEMIXING OF EUTECTOID MATERIAL; REFINING BY ZONE-MELTING OF MATERIAL; PRODUCTION OF A HOMOGENEOUS POLYCRYSTALLINE MATERIAL WITH DEFINED STRUCTURE; SINGLE CRYSTALS OR HOMOGENEOUS POLYCRYSTALLINE MATERIAL WITH DEFINED STRUCTURE; AFTER-TREATMENT OF SINGLE CRYSTALS OR A HOMOGENEOUS POLYCRYSTALLINE MATERIAL WITH DEFINED STRUCTURE; APPARATUS THEREFOR
- C30B29/00—Single crystals or homogeneous polycrystalline material with defined structure characterised by the material or by their shape
- C30B29/10—Inorganic compounds or compositions
- C30B29/36—Carbides
-
- C—CHEMISTRY; METALLURGY
- C30—CRYSTAL GROWTH
- C30B—SINGLE-CRYSTAL GROWTH; UNIDIRECTIONAL SOLIDIFICATION OF EUTECTIC MATERIAL OR UNIDIRECTIONAL DEMIXING OF EUTECTOID MATERIAL; REFINING BY ZONE-MELTING OF MATERIAL; PRODUCTION OF A HOMOGENEOUS POLYCRYSTALLINE MATERIAL WITH DEFINED STRUCTURE; SINGLE CRYSTALS OR HOMOGENEOUS POLYCRYSTALLINE MATERIAL WITH DEFINED STRUCTURE; AFTER-TREATMENT OF SINGLE CRYSTALS OR A HOMOGENEOUS POLYCRYSTALLINE MATERIAL WITH DEFINED STRUCTURE; APPARATUS THEREFOR
- C30B7/00—Single-crystal growth from solutions using solvents which are liquid at normal temperature, e.g. aqueous solutions
Abstract
The invention relates to the technical field of silicon carbide single crystals, in particular to a method and a device for growing silicon carbide single crystals by a liquid phase method. A method for growing a silicon carbide single crystal by a liquid phase method, comprising: under the vacuum environment, controlling the seed crystal to move towards the liquid growth raw material; monitoring whether the seed crystal is subjected to forces from the growing feedstock; upon monitoring the force of the seed crystal against the growing material, stopping movement of the seed crystal to grow a single crystal of silicon carbide at the interface of the seed crystal and the growing material. The embodiment of the invention provides a growth method and a growth device for growing a silicon carbide single crystal by a liquid phase method, and can provide a growth method and a growth device for accurately judging whether a seed crystal just contacts with a liquid level.
Description
Technical Field
The invention relates to the technical field of silicon carbide single crystals, in particular to a method and a device for growing silicon carbide single crystals by a liquid phase method.
Background
Silicon carbide (SiC) is one of the most important third-generation semiconductor materials, and due to the characteristics of large specific forbidden bandwidth, high critical breakdown field strength and the like, the SiC becomes an ideal material for manufacturing high-frequency, high-power, anti-irradiation and illumination integrated devices, and is widely applied to a plurality of fields such as new energy automobiles, 5G communication, aerospace and the like.
In the related art, the growth of silicon carbide single crystal by liquid phase method is a novel means for preparing silicon carbide single crystal, and solid seed crystal is required to be contacted with liquid growth raw material, and the silicon carbide single crystal grows at the solid-liquid contact interface. The liquid phase method is used for growing the silicon carbide single crystal, the seed crystal needs to contact the liquid surface of the high-temperature molten growth raw material under the control of equipment, the growth raw material comprises carbon atoms and silicon atoms, the carbon atoms and the silicon atoms are orderly arranged at a solid-liquid interface under the limiting action of the seed crystal, and finally the silicon carbide crystal ingot is grown. However, since the growth of silicon carbide needs to be carried out in a completely closed device, whether the seed crystal is just in contact with the liquid level or not cannot be accurately judged, and the defect of the extension process can seriously affect the crystal quality.
Therefore, in view of the above disadvantages, there is a high necessity for a method and an apparatus for growing a silicon carbide single crystal by a liquid phase method.
Disclosure of Invention
The embodiment of the invention provides a device and a method for growing a silicon carbide single crystal by a liquid phase method, and provides a lengthening method and a lengthening device for accurately judging whether a seed crystal just contacts with a liquid level.
In a first aspect, an embodiment of the present invention provides a method for growing a silicon carbide single crystal by a liquid phase method, including:
under the vacuum environment, controlling the seed crystal to move towards the liquid growth raw material;
monitoring whether the seed crystal is subjected to forces from the growing feedstock;
upon monitoring the force of the seed crystal against the growing material, stopping movement of the seed crystal to grow a single crystal of silicon carbide at the interface of the seed crystal and the growing material.
In one possible design, further comprising:
when the force of the seed crystal to the growing raw material is monitored, controlling the seed crystal to move in a direction away from the growing raw material;
stopping the movement of the seed crystal when the distance between the seed crystal and the liquid level of the growth raw material is a preset distance, so that the silicon carbide single crystal grows on the interface of the seed crystal and the growth raw material; when the distance between the seed crystal and the liquid level of the growth raw material is a preset distance, the seed crystal can adsorb the growth raw material liquid to form a meniscus.
In one possible design, further comprising:
when the force of the seed crystal on the growth raw material is monitored, controlling the seed crystal to be submerged 5-15 mm below the liquid level of the growth raw material;
controlling the seed crystal to move away from the growth raw material;
stopping the movement of the seed crystal when the distance between the seed crystal and the liquid level of the growth raw material is a preset distance, so that the silicon carbide single crystal grows on the interface of the seed crystal and the growth raw material; when the distance between the seed crystal and the liquid level of the growth raw material is a preset distance, the seed crystal can adsorb the growth raw material liquid to form a meniscus.
In one possible design, before the controlling the seed crystal to move to the liquid growth feedstock, the method further comprises:
the growth raw material is subjected to a heating treatment so that the growth raw material melts and reaches a growth temperature of the silicon carbide single crystal.
In one possible design, the monitoring whether the seed crystal is subjected to a force from the growth feedstock comprises:
monitoring whether the seed crystal is subjected to an upward force from the growing raw material by using a gravity sensing device; wherein the seed crystal is subjected to an upward force from the growing feedstock as the data monitored by the gravity sensing device begins to diminish.
In one possible design, the monitoring whether the seed crystal is subjected to a force from the growth feedstock comprises:
monitoring whether the seed crystal is subjected to an upward force from the growing raw material by using a gravity sensing device; wherein the seed crystal is subjected to an upward force from the growing material when the data monitored by the gravity sensing device begins to be less than a standard value, the standard value being a value displayed by the gravity sensing device when the seed crystal is not moved prior to heating the growing material.
In one possible design, the measurement accuracy of the gravity sensing device is no greater than 0.12 g.
In one possible design, the predetermined distance is determined by:
collecting the stress of the seed crystal by using a gravity sensing device;
when the data acquired by the gravity sensing device is preset data, the seed crystal moves to the preset distance; the preset data is the sum of a standard value and the gravity of the growth raw material adsorbed by the seed crystal at the preset distance, and the standard value is a numerical value displayed by the gravity sensing device when the seed crystal is not moved before the growth raw material is heated.
In one possible design, the predetermined distance is 1 to 5 mm.
In a second aspect, an embodiment of the present invention provides an apparatus for growing a silicon carbide single crystal by a liquid phase method, for implementing the method according to any one of the first aspect, including:
the crucible is used for containing growth raw materials;
the tray is connected with seed crystals on one side facing the growth raw materials;
the transmission rod is connected with the tray and is used for controlling the tray to ascend, descend and rotate;
the transmission machine is connected with the transmission rod and used for providing power for the transmission rod;
a heating furnace for heating the crucible;
and the gravity sensing device is arranged in the transmission rod and is used for monitoring the force applied to the seed crystal.
Compared with the prior art, the invention at least has the following beneficial effects:
in this embodiment, under the vacuum environment, the seed crystal is controlled to move towards the liquid growth raw material, whether the seed crystal receives the force from the growth raw material is monitored in the moving process, when the seed crystal is monitored to receive the force from the growth raw material, the seed crystal is proved to be just in contact with the growth raw material, the seed crystal is stopped moving at the moment, the seed crystal is prevented from being completely immersed in the growth raw material, and then the high-quality silicon carbide single crystal cannot be grown. Whether the seed crystal just contacts with the liquid level can be accurately judged by monitoring the stress condition of the seed crystal, and then higher yield of the silicon carbide crystal can be obtained.
Drawings
In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below, and it is obvious that the drawings in the following description are some embodiments of the present invention, and for those skilled in the art, other drawings can be obtained according to these drawings without creative efforts.
FIG. 1 is a flowchart of a method for growing a silicon carbide single crystal by a liquid phase method according to an embodiment of the present invention;
FIG. 2 is a flowchart of another method for growing a silicon carbide single crystal by a liquid phase method according to an embodiment of the present invention;
FIG. 3 is a schematic view of a good meniscus formed between a seed crystal and the growth feedstock level provided by an embodiment of the present invention;
FIG. 4 is a schematic view of a seed crystal being immersed in a growth feedstock;
FIG. 5 is a schematic diagram showing the structure of an apparatus for growing a silicon carbide single crystal by a liquid phase method according to an embodiment of the present invention.
In the figure:
1-a crucible;
11-a cover body;
2-a tray;
3-a transmission rod;
4-a gravity sensing device;
5-growth raw material.
Detailed Description
In order to make the objects, technical solutions and advantages of the embodiments of the present invention clearer and more complete, the technical solutions in the embodiments of the present invention will be described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are some, but not all, embodiments of the present invention, and based on the embodiments of the present invention, all other embodiments obtained by a person of ordinary skill in the art without creative efforts belong to the scope of the present invention.
In the description of the embodiments of the present invention, unless explicitly specified or limited otherwise, the terms "first", "second", and the like are used for descriptive purposes only and are not to be construed as indicating or implying relative importance; the term "plurality" means two or more unless specified or indicated otherwise; the terms "connected," "fixed," and the like are to be construed broadly and may, for example, be fixedly connected, detachably connected, integrally connected, or electrically connected; may be directly connected or indirectly connected through an intermediate. The specific meanings of the above terms in the present invention can be understood by those skilled in the art according to specific situations.
In the description of the present invention, it should be understood that the terms "upper" and "lower" as used in the description of the embodiments of the present invention are used in the angle shown in the drawings, and should not be construed as limiting the embodiments of the present invention. In addition, in this context, it will also be understood that when an element is referred to as being "on" or "under" another element, it can be directly on "or" under "the other element or be indirectly on" or "under" the other element via an intermediate element.
As shown in fig. 1, an embodiment of the present invention provides a method for growing a silicon carbide single crystal by a liquid phase method, including:
and 104, stopping the movement of the seed crystal when the force of the growing raw material on the seed crystal is monitored, so that the silicon carbide single crystal grows on the interface of the seed crystal and the growing raw material.
In this embodiment, under the vacuum environment, the seed crystal is controlled to move towards the liquid growth raw material, whether the seed crystal receives the force from the growth raw material is monitored in the moving process, when the seed crystal is monitored to receive the force from the growth raw material, the seed crystal is proved to be just in contact with the growth raw material, the seed crystal is stopped moving at the moment, the seed crystal is prevented from being completely immersed in the growth raw material, and then the high-quality silicon carbide single crystal cannot be grown. Whether the seed crystal just contacts the liquid level can be accurately judged by monitoring the stress condition of the seed crystal, and then higher silicon carbide crystal yield can be obtained.
In this embodiment, the vacuum environment may be filled with a shielding gas, which includes at least one of helium, nitrogen, and argon.
In this embodiment, the growth raw material includes a carbon element and a silicon element, and at least one of Al, Ti, Cr, Fe, Y, Yb, Pr, La, Cu, Ce, Sn, Ge, and Co may be doped into the growth raw material.
It is understood that the method provided by the present embodiment can also be applied to the growth of silicon single crystal by liquid phase method.
The seed crystal is in a sheet shape, the thickness of the seed crystal is 0.3-0.7 mm, and in order to facilitate monitoring of the stress of the seed crystal and maximize the growth area of the silicon carbide single crystal, the seed crystal and the liquid level of the growth raw material need to be arranged in parallel when the seed crystal is moved.
As shown in fig. 3, in some embodiments of the invention, further comprising:
when the force of the growing raw material on the seed crystal is monitored, the seed crystal is controlled to move towards the direction far away from the growing raw material;
stopping the movement of the seed crystal when the distance between the seed crystal and the liquid level of the growth raw material is a preset distance, so that the silicon carbide single crystal grows on the interface of the seed crystal and the growth raw material; when the distance between the seed crystal and the liquid level of the growth raw material is a preset distance, the seed crystal can adsorb the growth raw material liquid to form a meniscus.
In this embodiment, after the seed crystal is contacted with the liquid level of the growth raw material, the direction of the seed crystal is controlled to move away from the growth raw material, so that the seed crystal adsorbs a part of the growth raw material to be lifted simultaneously with the growth raw material, and a meniscus is formed. The radiation heat dissipation of the meniscus enables the interface of the seed crystal and the growth raw material to be in a special temperature field, and the temperature field enables the silicon carbide single crystal to proceed from the periphery to the center, so that the silicon carbide single crystal with high crystal yield is obtained. Of course, a good silicon carbide single crystal can be obtained without controlling the seed crystal to rise to the preset distance, but compared with the solution without the meniscus, the solution with the meniscus has a higher yield of the silicon carbide crystal.
It should be noted that, in the prior art, it cannot be accurately determined whether the seed crystal just contacts the liquid level of the growth raw material, and if the seed crystal is submerged by the growth raw material, a meniscus cannot be generated, and the beneficial effect generated by the meniscus cannot be obtained.
In some embodiments of the invention, further comprising:
when the force of the growth raw material on the seed crystal is monitored, controlling the seed crystal to be submerged 5-15 mm below the liquid level of the growth raw material;
controlling the seed crystal direction to move away from the direction of the growth raw material;
stopping the movement of the seed crystal when the distance between the seed crystal and the liquid level of the growth raw material is a preset distance, so that the silicon carbide single crystal grows on the interface of the seed crystal and the growth raw material; when the distance between the seed crystal and the liquid level of the growth raw material is a preset distance, the seed crystal can adsorb the growth raw material liquid to form a meniscus.
In this embodiment, when monitoring that the seed crystal receives the power of growth raw materials, the seed crystal just contacts with the liquid level, use this position as the starting point, continue to move the seed crystal 5 ~ 15mm downwards, make inside the seed crystal gets into the growth raw materials, inside growth raw materials has higher temperature, so, can get rid of the partial ablation defect that the seed crystal surface formed, this ablation defect is that volatile growth raw materials cause at seed crystal surface reaction, submerge the seed crystal of partial ablation inside the higher growth raw materials of temperature, the ablation defect that the seed crystal can be got rid of to the growth raw materials of high temperature makes the seed crystal surface more level and more smooth. And after the ablation defect is removed, the seed crystal is moved to a preset distance to carry out the growth of the silicon carbide single crystal, and the seed crystal with excellent quality can be obtained on the smooth surface of the seed crystal.
In some embodiments of the invention, prior to controlling the movement of the seed crystal toward the liquid growth feedstock, further comprising:
the growth raw material is subjected to a heating treatment to melt the growth raw material and reach a growth temperature of the silicon carbide single crystal.
In this embodiment, the growth raw material is subjected to a heating treatment so that the growth raw material can be sufficiently melted, and the temperature of the growth raw material is raised to the growth temperature of the silicon carbide single crystal to enable rapid formation of the silicon carbide single crystal when the seed crystal and the growth raw material are brought into contact in the subsequent step. The preset temperature is preferably 1900-2100 ℃.
In some embodiments of the invention, monitoring whether the seed crystal is subjected to forces from the growth feedstock comprises:
monitoring whether the seed crystal is subjected to an upward force from the growing raw material by using a gravity sensing device; wherein the seed crystal is subjected to a force from the growth feedstock as the data monitored by the gravity sensing device begins to diminish.
In this embodiment, a gravity sensing device is used to monitor whether the seed crystal is subjected to an upward force from the growing material, including an upward buoyant force; the gravity sensing device can monitor the stress of the seed crystal in real time, has excellent sensitivity, and can accurately judge whether the seed crystal is stressed by the upward force of the growing raw material. When the seed crystal is completely contacted with the liquid level of the growth raw material, the seed crystal is subjected to upward force of the growth raw material, and the numerical value monitored by the gravity sensing device is reduced, so that when the numerical value monitored by the gravity sensing device is reduced, the contact between the seed crystal and the growth raw material can be proved, and the effect of accurately judging whether the seed crystal is contacted with the growth raw material is realized.
In some embodiments of the invention, monitoring whether the seed crystal is subjected to an upward force from the growing feedstock comprises:
monitoring whether the seed crystal is subjected to an upward force from the growing raw material by using a gravity sensing device; wherein, when the data monitored by the gravity sensing device is less than a standard value, the seed crystal is forced upwards by the growing raw material, and the standard value is a numerical value displayed by the gravity sensing device when the seed crystal is not moved before the growing raw material is heated.
In this embodiment, because the gravity inductor needs to be set up in the transfer line, consequently, the numerical value that the gravity inductor shows is the gravity of transfer line, tray and seed crystal, and the numerical value is great, in order to facilitate observing the abrupt change point of seed crystal and liquid level contact, can set for the standard value in the gravity inductor, furthermore, can set for the standard value 0 value (only in the system through the controller with the numerical value of standard value transfer to 0, the atress that does not change the seed crystal transfers 0), so set up, when the numerical value that the gravity induction system monitored is the negative value, can judge that the seed crystal just contacts with growth raw materials liquid level. The moment when the seed crystal contacts the growth raw material can be observed more visually by setting the standard value, particularly the standard value to 0.
In some embodiments of the present invention, the gravity sensing device has a measurement accuracy of no greater than 0.12 g.
In this embodiment, in order to accurately monitor the moment when the growing raw material liquid surface applies force to the seed crystal, the gravity sensing device is required to have excellent sensing and measuring accuracy, and if the measuring accuracy of the gravity sensing device is greater than 0.12g, the gravity sensing device cannot timely sense the upward force of the growing raw material, so that the moment when the seed crystal contacts the growing raw material cannot be accurately determined. In the present embodiment, the measurement accuracy of the gravity sensing device is preferably 0.1 g.
In some embodiments of the invention, the preset distance is determined by:
collecting stress of the seed crystal by using a gravity sensing device;
when the data acquired by the gravity sensing device is preset data, the seed crystal moves to a preset distance; the preset data is the sum of a standard value and the gravity of the growth raw material adsorbed by the seed crystal at a preset distance, and the standard value is a numerical value displayed by the gravity sensing device when the seed crystal is not moved before the growth raw material is heated.
In this embodiment, utilize gravity induction system to gather the atress of seed crystal, and then can confirm the distance of the meniscus that the absorption growth raw materials of seed crystal formed through the numerical value that gravity induction system gathered. Specifically, the direction that keeps away from the growth raw materials after the seed crystal contacts with the growth raw materials removes, at the in-process that removes, the seed crystal adsorbs partial growth raw materials and removes jointly, form the meniscus, the numerical value that gravity induction system gathered constantly increases, the data of gathering this moment include the standard value and the gravity that forms the partial growth raw materials of meniscus, the standard value is unchangeable, absorbent growth raw materials increases along with the rising of seed crystal, the gravity of absorbent growth raw materials also constantly increases, therefore, this seed crystal removes the in-process, gravity induction system's growth volume is the gravity growth volume that forms meniscus growth raw materials promptly. According to the height of the preset distance, the bottom area of the seed crystal and the density of the growing raw material, the gravity of the growing raw material forming the meniscus when the seed crystal reaches the preset height can be calculated, the sum of the standard value and the gravity of the seed crystal is used as the preset value of the gravity sensing device, and when the data collected by the gravity sensing device is equal to the preset value, the seed crystal can be judged to reach the preset distance.
It should be noted that, the optimal growth distances of the silicon carbide single crystal of the growth raw material doped with different elements are different, and the meniscus distance optimal for the growth of the silicon carbide single crystal can be obtained from a plurality of experiments and determined as the preset distance.
In some embodiments of the present invention, the predetermined distance is 1-5 mm.
In the embodiment, the predetermined distance is 1 to 5mm, which is preferable for the growth raw material doped with Cr and Al.
As shown in fig. 2, another method for growing a silicon carbide single crystal by a liquid phase method according to an embodiment of the present invention includes:
202, controlling the seed crystal to move towards the liquid growth raw material in a vacuum environment;
and step 210, when the distance between the seed crystal and the liquid level of the growth raw material is a preset distance, stopping the movement of the seed crystal so as to grow the silicon carbide single crystal on the interface of the seed crystal and the growth raw material.
In a second aspect, as shown in fig. 5, an embodiment of the present invention provides an extension apparatus for growing a silicon carbide single crystal by a liquid phase method, for implementing the method of any one of the first aspects, including:
a crucible 1 for holding growth raw material 5;
a tray 2, one side facing the growth raw material 5 is connected with seed crystals;
the transmission rod 3 is connected with the tray 2, and the transmission rod 3 is used for controlling the tray 2 to ascend, descend and rotate;
the transmission machine is connected with the transmission rod 3 and used for providing power for the transmission rod 3;
a heating furnace for heating the crucible 1;
and the gravity sensing device 4 is arranged in the transmission rod 3, and the gravity sensing device 4 is used for monitoring the force applied to the seed crystal.
In this embodiment, the crucible 1 may include a cover 11, and a through hole having a diameter of 50 to 160mm is formed in the middle of the cover 11 for passing the transmission rod 3. The wall thickness of the crucible 1 is 10-30 mm, and the bottom thickness is 15-40 mm. The tray 2 can be circular ring-shaped or cylindrical, the thickness is 5-50 mm, the preparation material comprises silicon carbide ceramic or graphite, and the tray 2 is bonded with the seed crystal. The axial length of the transmission rod 3 is 150-700 mm, and the radial length is 5-50 mm. The transmission machine may be a servo motor.
It is understood that the apparatus provided in this embodiment can also be applied to the growth of a silicon single crystal by a liquid phase method.
In some embodiments of the invention, the preparation material of the crucible 1 comprises graphite.
In the present example, the crucible 1 is made of a material having a purity of more than 99% and a density of more than 1.5g/cm 2 The graphite of (4). Graphite is selected as a preparation material of the crucible 1, when the crucible 1 is heated, carbon element in the crucible 1 can be dissolved into liquid in the crucible 1 until carbon in the solution is saturated, and thus, the carbon element can be dissolved in the liquidThe problem of adding a carbon-containing raw material is not considered when the crucible 1 is used as a carbon source.
In order to more clearly illustrate the technical solution and the advantages of the present invention, the following describes the advantages of the solution by comparing several prior arts.
Comparative example 1
Empirical method, the concrete method is as follows:
1. filling growth raw materials into a crucible, covering the crucible with a crucible cover, putting the crucible into a crystal growth furnace, and controlling a transmission rod through a transmission gear to put a tray adhered with seed crystals into the crucible;
2. after the crystal growth furnace is subjected to operations such as vacuumizing, inflating and the like, starting power to heat;
3. after the temperature or time reaches a preset value, controlling the seed crystal to descend through a transmission machine, judging a liquid receiving position according to a large-scale experiment result, and continuously moving downwards for 5-8mm after moving to the position;
and 4, controlling the seed crystal to ascend to the judged liquid receiving position through a transmission machine, and then carrying out crystal growth.
The scheme of comparative example 1 requires analysis and judgment of the liquid receiving position through a large amount of experimental data, and when the position of the growth crucible is slightly changed or the change of the raw material is required according to the experiment, the liquid receiving position becomes difficult to find, and the experiment needs to be performed on the basis of a new situation to obtain an approximate position. The silicon carbide single crystal grown by the empirical method cannot ensure that liquid is received at the optimal liquid receiving position every time, and errors of every time are different, so that the optimal meniscus searched according to the liquid receiving position cannot be ensured.
Experiments show that the error of finding the optimal liquid receiving position is 0-0.5 mm in the scheme, and the error of finding the optimal liquid receiving position is 0.8-7 mm in the scheme of the comparative example 1, which is difficult to control. The optimal liquid receiving position (namely the preset distance) is found by the scheme for single crystal growth, the crystal yield is about 90 percent, and the optimal liquid receiving position is found by the comparative example 1 for single crystal growth, and the crystal yield is about 35 percent.
Comparative example 2
The infrared temperature measurement method comprises the following specific steps:
1. filling growth raw materials into a crucible, covering the crucible with a crucible cover, putting the crucible into a crystal growth furnace, and controlling a transmission rod through a transmission gear to put a tray adhered with seed crystals into the crucible;
2. after the crystal growth furnace is subjected to operations such as vacuumizing, inflating and the like, the power is started to raise the temperature;
3. after the temperature or the time reaches a preset value, controlling the seed crystal to descend through a transmission gear, measuring the temperature change by utilizing infrared temperature measurement to judge whether the seed crystal is contacted with a growth raw material or not, wherein heat transfer occurs when the seed crystal is contacted with the growth raw material, and the measured temperature is suddenly changed to indicate that liquid receiving is completed;
4. and locking the height of the meniscus according to the liquid receiving position, and then performing crystal growth.
The solution of comparative example 2 requires a sudden temperature change to reflect the contact of the seed crystal with the liquid surface, and there are many influencing factors such as: the effect is poor when the seed crystal is bonded, the temperature transmission is influenced, the deviation between the feedback position and the actual position is forced, the seed crystal is immersed in the liquid level, and the meniscus can not be obtained; temperature measuring points are selected differently, and the temperature transmission speed at different points is possibly deviated, so that the feedback position is deviated from the actual position, the seed crystal is immersed in the liquid level (figure 4), and the liquid level cannot be obtained; the thickness of the seed crystal, the shape, the thickness and the size of the seed crystal tray are different, the temperature transfer speed has deviation, and the feedback position has deviation with the actual position, so that the seed crystal is immersed in the liquid level and the meniscus can not be obtained. The silicon carbide single crystal grown by the infrared temperature measurement method cannot ensure that liquid is received at the optimal liquid receiving position every time, and errors of every time cannot be ensured according to different external influence factors, so that the optimal meniscus searched according to the liquid receiving position cannot be ensured.
Experiments show that the error of finding the optimal liquid receiving position is 0-0.5 mm in the scheme, and the error of finding the optimal liquid receiving position is 0.8-4 mm in the scheme of the comparative example 2, which is difficult to control. The optimal liquid receiving position (namely the preset distance) is found through the scheme for carrying out the single crystal growth, the crystal yield is about 90 percent, and the optimal liquid receiving position is found in the comparative example 2 for carrying out the single crystal growth, and the crystal yield is about 65 percent.
Finally, it should be noted that: the above examples are only intended to illustrate the technical solution of the present invention, but not to limit it; although the present invention has been described in detail with reference to the foregoing embodiments, it will be understood by those of ordinary skill in the art that: the technical solutions described in the foregoing embodiments may still be modified, or some technical features may be equivalently replaced; and such modifications or substitutions do not depart from the spirit and scope of the corresponding technical solutions of the embodiments of the present invention.
Claims (10)
1. A method for growing a silicon carbide single crystal by a liquid phase method, comprising:
under the vacuum environment, controlling the seed crystal to move towards the liquid growth raw material;
monitoring whether the seed crystal is subjected to forces from the growing feedstock;
upon monitoring the force of the seed crystal against the growing material, stopping movement of the seed crystal to grow a single crystal of silicon carbide at the interface of the seed crystal and the growing material.
2. The method of claim 1, further comprising:
when the force of the seed crystal to the growing raw material is monitored, controlling the seed crystal to move in a direction away from the growing raw material;
stopping the movement of the seed crystal when the distance between the seed crystal and the liquid level of the growth raw material is a preset distance, so that the silicon carbide single crystal grows on the interface of the seed crystal and the growth raw material; when the distance between the seed crystal and the liquid level of the growth raw material is a preset distance, the seed crystal can adsorb the growth raw material liquid to form a meniscus.
3. The method of claim 1, further comprising:
when the force of the seed crystal on the growth raw material is monitored, controlling the seed crystal to be submerged 5-15 mm below the liquid level of the growth raw material;
controlling the seed crystal to move away from the growth raw material;
stopping the movement of the seed crystal when the distance between the seed crystal and the liquid level of the growth raw material is a preset distance, so that the silicon carbide single crystal grows on the interface of the seed crystal and the growth raw material; when the distance between the seed crystal and the liquid level of the growth raw material is a preset distance, the seed crystal can adsorb the growth raw material liquid to form a meniscus.
4. The method of claim 1, further comprising, prior to said controlling movement of the seed crystal toward the liquid growth feedstock:
the growth raw material is subjected to a heating treatment so that the growth raw material melts and reaches a growth temperature of the silicon carbide single crystal.
5. The method of claim 1, wherein said monitoring whether said seed crystal is subjected to forces from said growth feedstock comprises:
monitoring whether the seed crystal is subjected to an upward force from the growing raw material by using a gravity sensing device; wherein the seed crystal is subjected to an upward force from the growing feedstock as the data monitored by the gravity sensing device begins to diminish.
6. The method of claim 1, wherein said monitoring whether said seed crystal is subjected to forces from said growth feedstock comprises:
monitoring whether the seed crystal is subjected to an upward force from the growing raw material by using a gravity sensing device; wherein said seed crystal is subjected to an upward force from said growing feedstock when the data monitored by said gravity sensing device begins to be less than a standard value, said standard value being a value displayed by said gravity sensing device when said seed crystal is not moved prior to heating said growing feedstock.
7. The method of claim 5 or 6, wherein the gravity sensing device has a measurement accuracy of no more than 0.12 g.
8. A method according to claim 2 or 3, characterized in that the preset distance is determined by:
collecting the stress of the seed crystal by using a gravity sensing device;
when the data acquired by the gravity sensing device is preset data, the seed crystal moves to the preset distance; the preset data is the sum of a standard value and the gravity of the growth raw material adsorbed by the seed crystal at the preset distance, and the standard value is a numerical value displayed by the gravity sensing device when the seed crystal is not moved before the growth raw material is heated.
9. The method of claim 8, wherein the predetermined distance is 1-5 mm.
10. An elongation apparatus for growing a silicon carbide single crystal by a liquid phase method, for carrying out the method according to any one of claims 1 to 9, comprising:
the crucible is used for containing growth raw materials;
the tray is connected with seed crystals on one side facing the growth raw materials;
the transmission rod is connected with the tray and is used for controlling the tray to ascend, descend and rotate;
the transmission machine is connected with the transmission rod and used for providing power for the transmission rod;
a heating furnace for heating the crucible;
and the gravity sensing device is arranged in the transmission rod and is used for monitoring the force applied to the seed crystal.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202210903128.3A CN115029781A (en) | 2022-07-29 | 2022-07-29 | Method and device for growing silicon carbide single crystal by liquid phase method |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202210903128.3A CN115029781A (en) | 2022-07-29 | 2022-07-29 | Method and device for growing silicon carbide single crystal by liquid phase method |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN115029781A true CN115029781A (en) | 2022-09-09 |
Family
ID=83130598
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202210903128.3A Pending CN115029781A (en) | 2022-07-29 | 2022-07-29 | Method and device for growing silicon carbide single crystal by liquid phase method |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN115029781A (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN116752237A (en) * | 2023-06-27 | 2023-09-15 | 通威微电子有限公司 | Seed crystal positioning method and crystal growth device |
Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US20160208409A1 (en) * | 2015-01-16 | 2016-07-21 | Toyota Jidosha Kabushiki Kaisha | Method for producing sic single crystal |
| CN106048713A (en) * | 2016-06-28 | 2016-10-26 | 山东天岳晶体材料有限公司 | Method for monitoring and regulating solid-liquid interface height in silicon carbide solution process in real time |
| CN114481318A (en) * | 2022-02-14 | 2022-05-13 | 北京青禾晶元半导体科技有限责任公司 | Method and device for controlling growth of silicon carbide crystals |
-
2022
- 2022-07-29 CN CN202210903128.3A patent/CN115029781A/en active Pending
Patent Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US20160208409A1 (en) * | 2015-01-16 | 2016-07-21 | Toyota Jidosha Kabushiki Kaisha | Method for producing sic single crystal |
| CN106048713A (en) * | 2016-06-28 | 2016-10-26 | 山东天岳晶体材料有限公司 | Method for monitoring and regulating solid-liquid interface height in silicon carbide solution process in real time |
| CN114481318A (en) * | 2022-02-14 | 2022-05-13 | 北京青禾晶元半导体科技有限责任公司 | Method and device for controlling growth of silicon carbide crystals |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN116752237A (en) * | 2023-06-27 | 2023-09-15 | 通威微电子有限公司 | Seed crystal positioning method and crystal growth device |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| KR101279756B1 (en) | System for continuous growing of monocrystalline silicon | |
| JP5803519B2 (en) | Method and apparatus for producing SiC single crystal | |
| US5714004A (en) | Process for producing polycrystalline semiconductors | |
| KR101805096B1 (en) | Methods and apparatus for making thin semiconductor bodies from molten material | |
| JP3388664B2 (en) | Method and apparatus for manufacturing polycrystalline semiconductor | |
| JP5434801B2 (en) | Method for producing SiC single crystal | |
| JPH107493A (en) | Production of silicon semiconductor substrate and substrate for solar cell | |
| CN115029781A (en) | Method and device for growing silicon carbide single crystal by liquid phase method | |
| JP6238249B2 (en) | Silicon carbide single crystal and method for producing the same | |
| JP3065076B1 (en) | Single crystal pulling method and single crystal pulling apparatus | |
| JP5163386B2 (en) | Silicon melt forming equipment | |
| JPH09249486A (en) | Method for pulling up single crystal | |
| KR20100056640A (en) | Single crystal growth apparatus | |
| CN116163007A (en) | Silicon carbide crystal growth device | |
| JP4899608B2 (en) | Semiconductor single crystal manufacturing apparatus and manufacturing method | |
| JP4184622B2 (en) | Method for producing silicon carbide single crystal ingot | |
| JP2720268B2 (en) | Single crystal pulling method and apparatus | |
| JP3498330B2 (en) | Single crystal growth equipment | |
| CN217709751U (en) | Germanium single crystal growth device by crucible descending method | |
| JP5053426B2 (en) | Silicon single crystal manufacturing method | |
| WO2011043777A1 (en) | Crystal growth apparatus and method | |
| JPH08290995A (en) | Silicon single crystal and its production | |
| JP2542434B2 (en) | Compound semiconductor crystal manufacturing method and manufacturing apparatus | |
| JPH09202685A (en) | Apparatus for pulling up single crystal | |
| WO2020044716A1 (en) | Single crystal growth method |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination |