Oxygen-reducing single crystal crucible with argon guide groove at bottom

Abstract

The utility model relates to the field of crucibles, in particular to an oxygen reduction single crystal crucible with an argon guide groove at the bottom. The utility model relates to an oxygen-reduction single crystal crucible with an argon guide groove at the bottom. The oxygen-reduction single crystal crucible comprises a graphite crucible body and a graphite support rod arranged at the bottom of the graphite crucible body, grooves which are radiated from the center to the outer edge are distributed on the inner side of the graphite crucible body, air outlet holes are distributed in the grooves, and the calibers of the air outlet holes are gradually increased from the central axis of the graphite crucible body to the outer edge of the graphite crucible body. A hollow structure of which the thickness is gradually increased from the central axis to the periphery is arranged in the graphite crucible body; and the hollow structure is communicated with the air outlet holes distributed in the grooves. The graphite supporting rod is connected with the crucible body at the center of the bottom of the graphite crucible body, a gas guide channel is arranged in the graphite supporting rod and serves as an argon guide groove, and an opening of the gas guide channel is communicated with the hollow structure in the graphite crucible body in the middle of the graphite crucible body.

Description

TECHNICAL FIELD

[0001] The utility model relates to the field of crucible, concretely relates to oxygen-reducing single crystal crucible. BACKGROUND

[0002] Monocrystalline silicon used for manufacturing integrated circuits and other electronic components is generally prepared by the Czochralski method. In the Czochralski method for manufacturing monocrystalline silicon, polycrystalline silicon is melted into liquid silicon at high temperature in a quartz crucible inside a graphite crucible, and then a seed crystal is lowered into the liquid silicon from the top, and the melted seed crystal is recrystallized around to form a single crystal silicon rod arranged in order by controlling the temperature of the liquid surface.

[0003] In the production of monocrystalline silicon, argon gas is used throughout the production process to protect the monocrystalline silicon. However, in the existing production process, the argon gas flow is not uniform, which can easily cause the phenomenon that the argon gas flow is stronger near the gas guide channel and weaker far from the gas guide channel, which can increase the harmful substances such as oxygen in the air entering the monocrystalline silicon product, and ultimately reduce the yield of the monocrystalline silicon product. SUMMARY

[0004] To solve at least one of the above technical problems, the utility model provides an oxygen-reducing single crystal crucible with an argon gas guide groove at the bottom.

[0005] The utility model can solve the above technical problems by using the following technical solutions:

[0006] The oxygen-reducing single crystal crucible with an argon gas guide groove at the bottom comprises a graphite crucible body and a graphite support rod arranged at the bottom of the graphite crucible body, characterized in that:

[0007] The graphite crucible body has gas outlet holes arranged at the bottom of the inner side, and the diameter of the gas outlet holes gradually increases from the central axis of the graphite crucible body to the outer edge of the graphite crucible body;

[0008] The graphite crucible body has a hollow structure with gradually increasing thickness from the central axis to the outer periphery, and the hollow structure is in communication with the gas outlet holes arranged at the bottom of the inner side of the graphite crucible body;

[0009] The graphite support rod is connected to the graphite crucible body at the center of the bottom of the outer side of the graphite crucible body;

[0010] The graphite support rod has a gas guide channel as an argon gas guide groove, and the opening of the gas guide channel is in communication with the hollow structure inside the graphite crucible body at the middle of the graphite crucible body.

[0011] The beneficial effect of the design is that the argon gas flow is adjusted when the Czochralski method is used to prepare the single crystal silicon, the argon gas flow near the gas guide channel is weakened within a certain range, the argon gas flow far from the gas guide channel is strengthened within a certain range, the argon gas flow is more uniform when the argon gas flows into the liquid silicon, and the oxygen content in the single crystal silicon far from the gas guide channel is reduced, thereby improving the yield of the single crystal silicon product.

[0012] Further, the graphite crucible is arranged outside the quartz crucible, the inner bottom of the graphite crucible is arranged with grooves radiating from the center to the outer edge, and the grooves are arranged with gas outlets; the outer bottom of the quartz crucible is arranged with protrusions radiating from the center to the outer edge, the protrusions are embedded in the grooves of the inner bottom of the graphite crucible; the protrusions are arranged with gas permeation holes communicating the outer bottom of the quartz crucible to the inner bottom of the quartz crucible, the height of the protrusions is less than the depth of the grooves, and the diameters of the corresponding gas outlets and gas permeation holes are consistent; the protrusions and the grooves form flow channels for the gas flow.

[0013] The beneficial effect of the design is that the flow channels are formed between the gas outlets of the graphite crucible and the gas permeation holes of the quartz crucible, the argon gas is introduced into the liquid silicon through the gas permeation holes in the bottom of the quartz crucible, the graphite crucible is not in direct contact with the liquid silicon, the reaction between the graphite crucible and the liquid silicon at high temperature is reduced, and the purity of the prepared single crystal silicon is improved.

[0014] Further, the length of the gas outlet arranged in the inner bottom of the graphite crucible is greater than 2mm, and the beneficial effect is that the direction of the argon gas flow is adjusted in the gas outlet arranged in the inner bottom of the graphite crucible, and the argon gas is made to flow towards the quartz crucible.

[0015] Further, the graphite crucible and the graphite support rod are connected firmly without loosening, and the bearing capacity is greater than 1500kg, and the beneficial effect is that a large amount of single crystal silicon can be prepared at one time, and the preparation cost of the single crystal silicon is reduced by reducing the number of preparation times.

[0016] Further, the graphite crucible and the graphite support rod are made of the same graphite material with the same expansion coefficient, so that the graphite crucible is not broken due to the different expansion coefficients during use, and the beneficial effect is that the safety of the preparation process is improved. BRIEF DESCRIPTION OF DRAWINGS

[0017] In order to more clearly illustrate the technical scheme of the embodiments of the present application, the drawings needed in the embodiment description will be briefly introduced as follows. Obviously, the drawings in the following description are only some embodiments of the present application, and other drawings can also be obtained by those skilled in the art without creative effort. Among them:

[0018] Figure 1 is a sectional view of the present application;

[0019] Figure 2 is a top view of the present application;

[0020] Figure 3 is a perspective view of the present application.

[0021] Number explanation:

[0022] 1, graphite pot body; 2, graphite support rod; 3, graphite bolt; 4, groove; 5, gas outlet hole; 6, hollow structure; 7, gas guide channel; 8, quartz crucible; 9, protrusion; 10, air hole; 11, liquid silicon. DETAILED DESCRIPTION

[0023] In order to make the above-mentioned purpose, features and advantages of the present application more apparent and easy to understand, the specific embodiments of the present application will be described in detail below with reference to the drawings of the specification.

[0024] In the following description, many specific details are set forth in order to provide a thorough understanding of the present application, but the present application can also be implemented in other ways different from those described herein, and those skilled in the art can make similar generalizations without departing from the connotation of the present application, therefore the present application is not limited by the specific embodiments disclosed below.

[0025] Secondly, the present application is described in detail in combination with the schematic diagram, in order to facilitate the description, the sectional view of the device structure will be partially enlarged without general proportion, and the schematic diagram is only an example, which should not limit the scope of protection of the present application here. In addition, the three-dimensional spatial dimensions of length, width and depth should be included in actual production.

[0026] Thirdly, the "one embodiment" or "embodiment" referred to herein can include specific features, structures or characteristics in at least one implementation of the present application. In this specification, "in one embodiment" does not mean the same embodiment, nor does it mean an embodiment that is separate or selectively excluded from other embodiments.

[0027] Figure 1 is a sectional view of the present application; Figure 2is a front view of the oxygen-reducing single crystal crucible, Figure 3 is a top view of the oxygen-reducing single crystal crucible.

[0028] Referring to Figure 1 , Figure 2 , Figure 3 The oxygen-reducing single crystal crucible with an argon gas guide groove at the bottom comprises a graphite crucible body 1 and a graphite supporting rod 2 arranged at the bottom of the graphite crucible body 1.

[0029] The graphite crucible body 1 is arranged with gas outlet holes 5 at the bottom inside, and the diameter of the gas outlet holes 5 gradually increases from the central axis of the graphite crucible body 1 to the outer edge of the graphite crucible body 1.

[0030] The graphite crucible body 1 has a hollow structure 6 inside, and the thickness of the hollow structure 6 gradually increases from the central axis to the outer edge, and the hollow structure 6 is in communication with the gas outlet holes 5 arranged at the bottom inside of the graphite crucible body 1.

[0031] The graphite supporting rod 2 is connected with the graphite crucible body 1 at the center of the bottom outside of the graphite crucible body 1.

[0032] The graphite supporting rod 2 has a gas guide channel 7 inside as the argon gas guide groove, and the opening of the gas guide channel 7 is in communication with the hollow structure 6 inside the graphite crucible body 1 at the middle of the graphite crucible body 1.

[0033] The graphite supporting rod 2 is fixed with the graphite crucible body 1 at the center of the bottom outside of the graphite crucible body 1 by using graphite bolts 3.

[0034] In the embodiment, the graphite crucible body 1 is arranged with gas outlet holes 5 at the bottom inside, the graphite crucible body 1 has a hollow structure 6 inside in communication with the gas outlet holes 5, and the diameter of the gas outlet holes 5 and the thickness of the hollow structure 6 gradually increase from the central axis of the graphite crucible body 1 to the outer edge of the graphite crucible body 1, which has the beneficial effect of adjusting the argon gas flow when using the Czochralski method to prepare single crystal silicon, weakening the argon gas flow near the gas guide channel 7 within a certain range, and strengthening the argon gas flow far from the gas guide channel 7 within a certain range, so that the argon gas flow is more uniform when the argon gas flows into the liquid silicon 11, which is beneficial to fully reduce the oxygen content in the single crystal silicon far from the gas guide channel, and ultimately improve the yield of single crystal silicon products.

[0035] Further, the graphite crucible body 1 is arranged outside the quartz crucible 8, the bottom inside of the graphite crucible body 1 is arranged with grooves 4 radiating from the center to the outer edge, and the grooves 4 are arranged with gas outlet holes 5; the bottom outside of the quartz crucible 8 is arranged with protrusions 9 radiating from the center to the outer edge, the protrusions 9 are embedded in the grooves 4 at the bottom inside of the graphite crucible body 1; the protrusions 9 are arranged with gas permeable holes 10 in communication from the bottom outside of the quartz crucible 8 to the bottom inside of the quartz crucible 8, the height of the protrusions 9 is less than the depth of the grooves 4, and the diameters of the corresponding gas outlet holes 5 and the gas permeable holes 10 are consistent; the protrusions 9 and the grooves 4 form flow channels for gas flow.

[0036] The beneficial effect is that the flow channel formed between the gas outlet hole 5 of the graphite crucible body 1 and the gas permeable hole 10 of the quartz crucible 8 allows argon gas to pass through the gas permeable hole 10 at the bottom of the quartz crucible 8 into the liquid silicon 11, and the graphite crucible body 1 is not in direct contact with the liquid silicon 11, reducing the reaction between the graphite crucible body 1 and the liquid silicon 11 at high temperature, and improving the purity of the prepared single crystal silicon.

[0037] The flow channel formed between the protrusion 9 and the groove 4 allows gas flow to pass through, instead of simply corresponding to the gas outlet hole 5 and the gas permeable hole 10, which is beneficial to improve the fault tolerance of processing precision.

[0038] The manufacturing difficulty is reduced, and the uniformity and stability of the gas flow supply can be maintained as a whole when one or several gas outlet holes 5 or gas permeable holes 10 are blocked.

[0039] Further, the length of the gas outlet hole 5 arranged at the inner bottom of the graphite crucible body 1 is greater than 2mm, which has the beneficial effect of facilitating the adjustment of the direction of argon gas flow in the gas outlet hole 5 arranged at the inner bottom of the graphite crucible body 1, promoting the flow of argon gas towards the quartz crucible 8, and appropriately increasing the gas flow impact force above the gas permeable hole 10, promoting the disturbance of the surrounding liquid silicon 11, and releasing oxygen molecules or oxygen atoms.

[0040] Further,

[0041] The diameter of the gas outlet hole 5 closest to the center of the graphite crucible body 1 is one to three times different from the diameter of the gas outlet hole 5 closest to the outer edge of the graphite crucible body 1.

[0042] The beneficial effect is that it is beneficial to increase the argon gas flow at the outer edge of the graphite crucible body 1, and more fully reduce the oxygen content in the liquid silicon above the outer edge of the graphite crucible body 1.

[0043] Further, the graphite crucible body 1 is firmly connected with the graphite support rod 2 without loosening, and the bearing capacity is greater than 1500kg, which has the beneficial effect of facilitating the preparation of a large amount of single crystal silicon at one time, and reducing the preparation cost of single crystal silicon by reducing the number of single crystal silicon preparation times.

[0044] Further, the graphite crucible body 1 and the support rod 2 are made of the same graphite material with the same expansion coefficient, which ensures that the graphite crucible does not break due to different expansion coefficients during use, and the beneficial effect is to improve the safety of the preparation process.

[0045] In addition, in order to provide a brief description of the exemplary embodiments, not all features of the actual embodiments can be described, i.e. those features that are not related to the currently considered best mode of carrying out the present application, or those features that are not related to the implementation of the present application.

[0046] It is to be understood that the development process can involve both substantial design and experimental efforts. As such, in embodiments of the application, design synthesis and / or experimental tests can be conducted to help improve the performance of the devices. Efforts can be directed to concurrently improving one or more performance characteristics of the devices.

[0047] It should be noted that the above examples are only used to illustrate the technical solutions of the present application but not limit the present application. Although the present application has been described in detail with reference to the preferred embodiments, those skilled in the art should understand that the technical solutions of the present application can be modified or equivalently replaced without departing from the spirit and scope of the present application, and all modifications and equivalent replacements should be included in the scope of the claims of the present application.

Claims

1. A single crystal crucible with an argon gas channel in the bottom, comprising a graphite crucible body and a graphite support rod arranged at the bottom of the graphite crucible body, characterized in that: the bottom of the inner side of the graphite crucible body is arranged with gas outlet holes, the diameter of the gas outlet holes gradually increases from the central axis of the graphite crucible body to the outer edge of the graphite crucible body; the graphite crucible body has a hollow structure with gradually increasing thickness from the central axis to the outer periphery, and the hollow structure is in communication with the gas outlet holes arranged at the bottom of the inner side of the graphite crucible body; the graphite support rod is connected to the graphite crucible body at the center of the bottom of the outer side of the graphite crucible body; the graphite support rod has a gas guide channel as the argon gas channel, and the opening of the gas guide channel is in communication with the hollow structure in the graphite crucible body at the middle of the graphite crucible body; the graphite crucible body is arranged outside a quartz crucible, the bottom of the inner side of the graphite crucible body is arranged with grooves radiating from the center to the outer edge, and the grooves are arranged with gas outlet holes; the bottom of the outer side of the quartz crucible is arranged with protrusions radiating from the center to the outer edge, and the protrusions are embedded in the grooves of the bottom of the inner side of the graphite crucible body; the protrusions are arranged with gas permeable holes for communication between the bottom of the outer side of the quartz crucible and the bottom of the inner side of the quartz crucible, the height of the protrusions is less than the depth of the grooves, and the diameters of the corresponding gas outlet holes and gas permeable holes are consistent; the protrusions and the grooves form a flow channel for gas flow. The length of the gas outlet holes arranged at the bottom of the inner side of the graphite crucible body is greater than 2 mm. The diameter of the gas outlet hole closest to the center of the graphite crucible body is one to three times different from the diameter of the gas outlet hole closest to the outer edge of the graphite crucible body. ​ ​ 2. The oxygen reduction single crystal crucible provided with an argon guide groove according to claim 1, wherein ​ ​ 3. The oxygen reduction single crystal crucible provided with an argon guide groove according to claim 2, wherein ​ 4. The oxygen-decreasing single crystal crucible provided with an argon gas guide groove according to claim 1, 2 or 3, characterized by, ​

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