TW202305202A - Monocrystalline silicon crystal pulling control method and device and monocrystalline silicon crystal pulling furnace - Google Patents

Abstract

The invention provides a monocrystalline silicon crystal pulling control method and device and a monocrystalline silicon crystal pulling furnace, and belongs to the technical field of semiconductors. The monocrystalline silicon crystal pulling control device comprises a power supply module, one end of the power supply module is connected with a crucible shaft, the other end of the power supply module is connected with a seed crystal pulling structure, and the power supply module is used for providing an electric signal to pull a crystal fixed by the seed crystal pulling structure to a silicon solution in a quartz crucible when the crystal contacts with the silicon solution in the quartz crucible; a current loop is formed among the crucible shaft, the quartz crucible, the graphite crucible, the silicon solution, the crystal and the seed crystal pulling structure; the measurement module is used for measuring an actual current value in the current loop in real time; and the control module is used for determining a target current value according to the target diameter of the tail part of the crystal, comparing the actual current value with the target current value, and controlling the crystal pulling speed of the seed crystal pulling structure and/or the power of the heater according to a comparison result. According to the invention, the diameter of the tail part of monocrystalline silicon can be controlled.

Description

Single crystal silicon crystal pulling control method and device, single crystal silicon crystal pulling furnace

The invention belongs to the technical field of semiconductors, in particular to a single crystal silicon crystal pulling control method and device, and a single crystal silicon crystal pulling furnace.

In the production process of single crystal silicon, the crystal is directly separated from the liquid surface after the crystal pulling process is completed, and the grown dislocation-free single crystal is subjected to thermal shock. When the thermal stress is greater than the critical stress of silicon, dislocations will be generated, causing the crystal to lose Complete single crystal structure, so it needs to be finished after the isodiameter is finished, so that the crystal and the liquid surface can be separated slowly, so as to avoid dislocation of the generated single crystal crystal due to thermal shock.

In the related technology, due to the limitation of the structure of the crystal pulling furnace and the special finishing procedure, it is impossible to monitor the solid-liquid interface at the finishing time by visual or other visual software, so the actual diameter of the crystal cannot be obtained, and the finishing procedure requires crystal The diameter of the crystal is gradually reduced and leaves the melt with the minimum contact surface to ensure that the crystal will not produce defects; in related technologies, the finishing procedure of crystal pulling is mainly carried out through the control system using a preset finishing procedure: when the single crystal finishing starts, the Single crystal pulling speed and temperature calibration value, and adjust the single crystal pulling speed and temperature calibration value according to the change of single crystal finishing length before the end of single crystal finishing. At the same time, it is necessary to always ensure that the solid-liquid interface is within the field of view to ensure that Lifting will occur, so the actual ending length will be longer, generally about 280~300mm, and the required time is about 8~10h. However, the above-mentioned finishing procedures cannot control the diameter of the tail of the single crystal silicon, and the change of the crystal diameter is directly related to the length and shape of the tail; if the diameter decreases too slowly, the length of the tail will be too long, resulting in the More, and the finishing time is long; if the diameter is reduced too fast, the length of the finishing is reduced. Although it is beneficial to reduce the finishing materials, increase the yield, reduce the finishing time, and reduce the consumption of electricity and argon, but the tail length is too short. It is easy to generate dislocations, and the crystal loses its complete single crystal structure.

The technical problem to be solved by the present invention is to provide a single crystal silicon crystal pulling control method and device, and a single crystal silicon crystal pulling furnace, which can control the diameter of the tail of the single crystal silicon.

In order to solve the above technical problems, embodiments of the present invention provide technical solutions as follows: On the one hand, an embodiment of the present invention provides a single crystal silicon crystal pulling control device, which is applied to a single crystal silicon crystal pulling furnace. The single crystal silicon crystal pulling furnace includes a furnace body, and the furnace body is provided with a crucible and a heater. The crucible is connected to There is a crucible shaft, and the crucible includes a quartz crucible for containing silicon solution, a graphite crucible wrapped outside the quartz crucible, and a seed crystal pulling structure located above the graphite crucible. The single crystal silicon crystal pulling control device includes: A power module, one end of the power module is connected to the crucible shaft, and the other end is connected to the seed crystal pulling structure, which is used to provide electrical signals for the crystal fixed in the seed crystal pulling structure and the silicon in the quartz crucible When the solutions are in contact, a current loop is formed between the crucible shaft, the quartz crucible, the graphite crucible, the silicon solution, the crystal and the seed crystal pulling structure; The measurement module is used to measure the actual current value in the current loop in real time; The control module is used to determine the target current value according to the target diameter of the crystal tail, compare the actual current value with the target current value, and control the crystal pulling speed of the seed crystal pulling structure and/or the heater according to the comparison result power.

In some embodiments, the control module is specifically used to increase the crystal pulling speed of the seed crystal pulling structure and/or the power of the heater when the actual current value is greater than the target current value; When it is less than the target current value, reduce the crystal pulling speed of the seed crystal pulling structure and/or the power of the heater.

In some embodiments, the control module is also used to acquire multiple sets of measurement data, and fit the corresponding relationship between the target diameter and the target current value according to the multiple sets of measurement data, and each set of measurement data includes at least the current loop The current value in , the diameter of the crystal tail and the varying length of the crystal tail.

The embodiment of the present invention also provides a single crystal silicon crystal pulling furnace, which includes a furnace body, a crucible and a heater are arranged in the furnace body, the crucible is connected with a crucible shaft, and the crucible includes a quartz crucible for containing silicon solution and a package The graphite crucible outside the quartz crucible and the seed crystal pulling structure above the graphite crucible also include the above-mentioned single crystal silicon pulling control device.

The embodiment of the present invention also provides a single crystal silicon crystal pulling control method, which is applied to a single crystal silicon crystal pulling furnace. The single crystal silicon crystal pulling furnace includes a furnace body. The furnace body is provided with a crucible and a heater. The crucible is connected There is a crucible shaft, and the crucible includes a quartz crucible for containing silicon solution, a graphite crucible wrapped outside the quartz crucible, and a seed crystal pulling structure located above the graphite crucible. The single crystal silicon pulling control method includes: Input electrical signals to the crucible shaft and the seed crystal pulling structure, so that when the crystal fixed by the seed crystal pulling structure is in contact with the silicon solution in the quartz crucible, the crucible shaft, the quartz crucible, the graphite crucible, A current loop is formed among the silicon solution, the crystal and the seed pulling structure; Instantly measure the actual current value in the current loop; Determine the target current value according to the target diameter of the crystal tail, compare the actual current value with the target current value, and control the crystal pulling speed of the seed crystal pulling structure and/or the power of the heater according to the comparison result.

In some embodiments, the method specifically includes: When the actual current value is greater than the target current value, increase the crystal pulling speed of the seed crystal pulling structure and/or the power of the heater; The crystal pulling speed of the pulling structure and/or the power of the heater.

In some embodiments, the method also includes: Obtain multiple sets of measurement data, and fit the corresponding relationship between the target diameter and the target current value according to the multiple sets of measurement data. Each set of measurement data includes at least the current value in the current loop, the diameter of the crystal tail and the crystal tail of varying lengths.

Embodiments of the present invention have the following beneficial effects: In the above scheme, by monitoring the current value in the current loop, it is possible to accurately determine the change in crystal diameter during the finishing process, and to adjust the crystal pulling speed and/or heater power of the seed crystal pulling structure in real time, so that the crystal tail The diameter can reach the target diameter, and this embodiment can realize automatic closing, reduce personnel costs, and increase production capacity.

In order for Ligui examiners to understand the technical characteristics, content and advantages of the present invention and the effects it can achieve, the present invention is hereby combined with the accompanying drawings and appendices, and is described in detail in the form of embodiments as follows, and the drawings used therein , the purpose of which is only for illustration and auxiliary instructions, and not necessarily the true proportion and precise configuration of the present invention after implementation, so it should not be interpreted based on the proportion and configuration relationship of the attached drawings, and limit the application of the present invention in actual implementation The scope is described first.

In the description of the embodiments of the present invention, it should be understood that the terms "length", "width", "upper", "lower", "front", "rear", "left", "right", "vertical" , "horizontal", "top", "bottom", "inner", "outer" and other indicated orientations or positional relationships are based on the orientations or positional relationships shown in the drawings, and are only for the convenience of describing the embodiments of the present invention and simplifying the description , rather than indicating or implying that the device or element referred to must have a particular orientation, be constructed and operate in a particular orientation, and thus should not be construed as limiting the invention.

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

The technical problem to be solved by the present invention is to provide a single crystal silicon crystal pulling control method and device, and a single crystal silicon crystal pulling furnace, which can control the diameter of the tail of the single crystal silicon.

An embodiment of the present invention provides a single crystal silicon crystal pulling control device, which is applied to a single crystal silicon crystal pulling furnace. The single crystal silicon crystal pulling furnace includes a furnace body. The furnace body is provided with a crucible and a heater. The crucible is connected to a crucible shaft. , the crucible includes a quartz crucible for holding a silicon solution, a graphite crucible wrapped outside the quartz crucible, and a seed crystal pulling structure located above the graphite crucible, and the single crystal silicon crystal pulling control device includes: A power module, one end of the power module is connected to the crucible shaft, and the other end is connected to the seed crystal pulling structure, which is used to provide electrical signals for the crystal fixed in the seed crystal pulling structure and the silicon in the quartz crucible When the solutions are in contact, a current loop is formed between the crucible shaft, the quartz crucible, the graphite crucible, the silicon solution, the crystal and the seed crystal pulling structure; The measurement module is used to measure the actual current value in the current loop in real time; The control module is used to determine the target current value according to the target diameter of the crystal tail, compare the actual current value with the target current value, and control the crystal pulling speed of the seed crystal pulling structure and/or the heater according to the comparison result power.

In this embodiment, by monitoring the current value in the current loop, it is possible to accurately determine the change in crystal diameter during the finishing process, and adjust the crystal pulling speed and/or heater power of the seed crystal pulling structure in real time, so that the crystal tail The diameter can reach the target diameter, and this embodiment can realize automatic closing, reduce personnel costs, and increase production capacity.

Fig. 1 is a structural schematic diagram of a single crystal silicon crystal pulling control device according to an embodiment of the present invention. As shown in Fig. 1, a single crystal silicon crystal pulling furnace includes a furnace body, a crucible and a heater are arranged in the furnace body, and the crucible is connected to a crucible shaft 7. The crucible includes a quartz crucible 5 for containing silicon solution, a graphite crucible 4 wrapped outside the quartz crucible 5 , and a seed crystal pulling structure 2 above the graphite crucible 4 . During the crystal pulling process, polysilicon is put into a quartz crucible 5 and heated and melted to become a silicon solution 6. A crystal 3 with a specific crystal orientation is fixed at the lower end of the seed crystal pulling structure 2. When pulling a single crystal silicon rod, Firstly, the crystal 3 is welded with the silicon solution 6, and enters the seeding stage; then, by adjusting the temperature of the silicon solution 6, the upward lifting speed of the crystal 3, etc., the single crystal silicon grows continuously through the shoulder-shoulder stage and the shoulder-turning stage, and finally pulls A monocrystalline silicon rod is produced.

In this embodiment, the power supply module 1 provides an external voltage, and the power supply module 1 is respectively connected to the seed crystal pulling structure 2 and the crucible shaft 7. Both the seed crystal pulling structure 2 and the crucible shaft 7 are conductors, and the crystal 3 (including When the narrow neck 301, the crystal shoulder 302, the crystal body 303 and the crystal tail 304) contact the silicon solution 6, the crucible axis 7, the quartz crucible 5, the graphite crucible 4, the silicon solution 6, the crystal 3 and the A current loop is formed between the seed crystal pulling structures 2, and the current is turned on. Specifically, the positive pole of the power module 1 may be connected to the seed crystal pulling structure 2, and the negative pole of the power module 1 may be connected to the crucible shaft 7; of course, It may be that the negative pole of the power module 1 is connected to the seed crystal pulling structure 2 , and the positive pole of the power module 1 is connected to the crucible shaft 7 .

As the finishing process continues, the contact area between the crystal 3 and the silicon solution 6 will gradually decrease, and the resistance in the current loop will change, so the current will also show a certain trend of change.

In this embodiment, the actual current value in the current loop can be measured in real time through the measurement module. In order to simplify the structure, the measurement module can be integrated into the power supply module.

In the current loop, the total voltage U is provided by the power module 1 and remains constant during the finishing process; the resistance R generated in the current loop can be divided into four items, as shown in Figure 1, where R1 is the seed crystal pull The resistance between structure 2 and the head of crystal 3 to the end of the equal diameter, when entering the finishing stage, the shape of the head of crystal 3 to the end of the equal diameter has been fixed, so R1 remains unchanged; R2 is the finishing process The middle is produced by the crystal tail that has been formed, and the resistance value will change with the length and diameter of the tail; R3 is the resistance generated by the silicon solution, and the silicon solution will also decrease with the growth of the tail during the finishing process. The resistance value changes with the contact surface between the silicon solution and the quartz crucible; R4 is the total resistance value of the quartz crucible, graphite crucible and crucible shaft, which can be regarded as a constant.

Figure 2 is a schematic diagram of the resistance change during the crystal finishing process, where R2 is the corresponding resistance of the crystal tail, Δl is the changing length of the crystal tail, Δd is the diameter of the contact surface between the crystal and the silicon solution, that is, the diameter of the crystal tail; D is the crystal, etc. The diameter of the diameter part.

In this embodiment, as shown in the formulas S01-S05: where S01 shows that under the condition of applied voltage, the loop current is inversely proportional to the total resistance. From the formula S02, it can be seen that the total resistance R is the sum of the resistances of different segments in the loop, and R2 in the closing process is the main change item; formula S03 shows that the change value of R2 ΔR2 is related to the change length Δl of the crystal tail and the contact area ΔS of the solid-liquid surface (the contact surface between the crystal and the silicon solution), where Δl can be obtained by measuring the crystal length measurement device, and ρ is the resistivity, which is the material characteristic parameter, which is a constant; the formula S04 shows the relationship between the solid-liquid surface contact area ΔS and the contact surface diameter (crystal tail diameter) Δd; based on the formulas S01-S04, the formula S05 can be obtained, and S05 reflects the loop current There is a proportional relationship between I and the contact surface diameter (crystal tail diameter) Δd.

Through multiple tests in advance, the relationship between the actual diameter and the actual current value can be compared, and a storage database can be established based on this, and the proportional relationship between the current and the ending diameter can be obtained by fitting, and the current and the ending diameter can be established through fitting comparison. The proportional relationship between, so that the immediate diameter value can be cycled directly through the current signal value.

In some embodiments, the control module is also used to acquire multiple sets of measurement data, and fit the corresponding relationship between the target diameter and the target current value according to the multiple sets of measurement data, and each set of measurement data includes at least the current loop The current value in , the diameter of the crystal tail and the varying length of the crystal tail.

After establishing the corresponding relationship between the target diameter and the target current value, the change value of the target diameter with the length can be input in advance during the closing process, and the corresponding target current value can be obtained by fitting conversion; the actual current value can be directly obtained during the closing process , compare it with the target current value, and control the crystal pulling speed of the seed crystal pulling structure and/or the power of the heater according to the comparison result.

In some embodiments, the control module is specifically used to increase the crystal pulling speed of the seed crystal pulling structure and/or the power of the heater when the actual current value is greater than the target current value; When it is less than the target current value, reduce the crystal pulling speed of the seed crystal pulling structure and/or the power of the heater.

When the actual current value is greater than the target current value, it means that the actual diameter is too large, which can be controlled by increasing the crystal pulling speed of the seed crystal pulling structure and/or the power of the heater to ensure that the actual diameter is close to or equal to the target diameter ; When the actual current value is less than the target current value, it means that the actual diameter is too small, which can be controlled by reducing the crystal pulling speed of the seed crystal pulling structure and/or the power of the heater to ensure that the actual diameter is close to the target diameter.

In this embodiment, a database of current-diameter changes in the finishing process can be established and obtained to realize automatic control of different finishing shape requirements; during the actual finishing process, the diameter of the ending is monitored according to the change of the actual current value to ensure that the finishing process is controllable. Improve the success rate of finishing; in addition, the diameter parameter at the time of finishing can be set in advance, and the relationship between the actual diameter and the set value can be compared in real time during the finishing process to control the finishing procedure in a loop, so as to achieve the purpose of automatic finishing, reduce personnel costs, and improve production capacity.

The embodiment of the present invention also provides a single crystal silicon crystal pulling furnace, which includes a furnace body, a crucible and a heater are arranged in the furnace body, the crucible is connected with a crucible shaft, and the crucible includes a quartz crucible for containing silicon solution and a package The graphite crucible outside the quartz crucible and the seed crystal pulling structure above the graphite crucible also include the above-mentioned single crystal silicon pulling control device.

The embodiment of the present invention also provides a single crystal silicon crystal pulling control method, which is applied to a single crystal silicon crystal pulling furnace. The single crystal silicon crystal pulling furnace includes a furnace body. The furnace body is provided with a crucible and a heater. The crucible is connected There is a crucible shaft, and the crucible includes a quartz crucible for containing silicon solution, a graphite crucible wrapped outside the quartz crucible, and a seed crystal pulling structure above the graphite crucible, as shown in Figure 3, the single crystal silicon pull Crystal control methods include: Step 101: Input electrical signals to the crucible shaft and the seed crystal pulling structure, so that when the crystal fixed by the seed crystal pulling structure contacts the silicon solution in the quartz crucible, the crucible shaft, the quartz crucible, and the A current loop is formed among the graphite crucible, the silicon solution, the crystal and the seed crystal pulling structure; Step 102: Immediately measure the actual current value in the current loop; Step 103: Determine the target current value according to the target diameter of the crystal tail, compare the actual current value with the target current value, and control the crystal pulling speed of the seed crystal pulling structure and/or the power of the heater according to the comparison result.

In this embodiment, by monitoring the current value in the current loop, it is possible to accurately determine the change in crystal diameter during the finishing process, and adjust the crystal pulling speed and/or heater power of the seed crystal pulling structure in real time, so that the crystal tail The diameter can reach the target diameter, and this embodiment can realize automatic closing, reduce personnel costs, and increase production capacity.

Fig. 1 is a structural schematic diagram of a single crystal silicon crystal pulling control device according to an embodiment of the present invention. As shown in Fig. 1, a single crystal silicon crystal pulling furnace includes a furnace body, a crucible and a heater are arranged in the furnace body, and the crucible is connected to a crucible shaft 7. The crucible includes a quartz crucible 5 for containing silicon solution, a graphite crucible 4 wrapped outside the quartz crucible 5 , and a seed crystal pulling structure 2 above the graphite crucible 4 . During the crystal pulling process, polysilicon is put into a quartz crucible 5 and heated and melted to become a silicon solution 6. A crystal 3 with a specific crystal orientation is fixed at the lower end of the seed crystal pulling structure 2. When pulling a single crystal silicon rod, Firstly, the crystal 3 is welded with the silicon solution 6, and enters the seeding stage; then, by adjusting the temperature of the silicon solution 6, the upward lifting speed of the crystal 3, etc., the single crystal silicon grows continuously through the shoulder-shoulder stage and the shoulder-turning stage, and finally pulls A monocrystalline silicon rod is produced.

In this embodiment, the power supply module 1 provides an external voltage, and the power supply module 1 is respectively connected to the seed crystal pulling structure 2 and the crucible shaft 7. Both the seed crystal pulling structure 2 and the crucible shaft 7 are conductors, and the crystal 3 (including Narrow neck 301, crystal shoulder 302, crystal main body 303 and crystal tail 304) contact with silicon solution 6, in the crucible shaft 7, the quartz crucible 5, the graphite crucible 4, the silicon solution 6, the crystal 3 and the A current loop is formed between the seed crystal pulling structures 2, and the current is turned on. Specifically, the positive pole of the power module 1 may be connected to the seed crystal pulling structure 2, and the negative pole of the power module 1 may be connected to the crucible shaft 7; of course, It may be that the negative pole of the power module 1 is connected to the seed crystal pulling structure 2 , and the positive pole of the power module 1 is connected to the crucible shaft 7 .

As the finishing process continues, the contact area between the crystal 3 and the silicon solution 6 will gradually decrease, and the resistance in the current loop will change, so the current will also show a certain trend of change.

In the current loop, the total voltage U is provided by the power module 1 and remains constant during the finishing process; the resistance R generated in the current loop can be divided into four items, as shown in Figure 1, where R1 is the seed crystal pull The resistance between structure 2 and the head of crystal 3 to the end of the equal diameter, when entering the finishing stage, the shape of the head of crystal 3 to the end of the equal diameter has been fixed, so R1 remains unchanged; R2 is the finishing process The middle is produced by the crystal tail that has been formed, and the resistance value will change with the length and diameter of the tail; R3 is the resistance generated by the silicon solution, and the silicon solution will also decrease with the growth of the tail during the finishing process. The resistance value changes with the contact surface between the silicon solution and the quartz crucible; R4 is the total resistance value of the quartz crucible, graphite crucible and crucible shaft, which can be regarded as a constant.

Figure 2 is a schematic diagram of the resistance change during the crystal finishing process, where R2 is the corresponding resistance of the crystal tail, Δl is the changing length of the crystal tail, Δd is the diameter of the contact surface between the crystal and the silicon solution, that is, the diameter of the crystal tail; D is the crystal, etc. The diameter of the diameter part.

In this embodiment, as shown in the formulas S01-S05: where S01 shows that under the condition of applied voltage, the loop current is inversely proportional to the total resistance. From the formula S02, it can be seen that the total resistance R is the sum of the resistances of different segments in the loop, and R2 in the closing process is the main change item; formula S03 shows that the change value of R2 ΔR2 is related to the change length Δl of the crystal tail and the contact area ΔS of the solid-liquid surface (the contact surface between the crystal and the silicon solution), where Δl can be obtained by measuring the crystal length measurement device, and ρ is the resistivity, which is the material characteristic parameter, which is a constant; the formula S04 shows the relationship between the solid-liquid surface contact area ΔS and the contact surface diameter (crystal tail diameter) Δd; based on the formulas S01-S04, the formula S05 can be obtained, and S05 reflects the loop current There is a proportional relationship between I and the contact surface diameter (crystal tail diameter) Δd.

Through multiple tests in advance, the relationship between the actual diameter and the actual current value can be compared, and a storage database can be established based on this, and the proportional relationship between the current and the ending diameter can be obtained by fitting, and the current and the ending diameter can be established through fitting comparison. The proportional relationship between, so that the immediate diameter value can be cycled directly through the current signal value.

In some embodiments, the method includes: Obtain multiple sets of measurement data, and fit the corresponding relationship between the target diameter and the target current value according to the multiple sets of measurement data. Each set of measurement data includes at least the current value in the current loop, the diameter of the crystal tail and the crystal tail of varying lengths.

After establishing the corresponding relationship between the target diameter and the target current value, the change value of the target diameter with the length can be input in advance during the closing process, and the corresponding target current value can be obtained by fitting conversion; the actual current value can be directly obtained during the closing process , compare it with the target current value, and control the crystal pulling speed of the seed crystal pulling structure and/or the power of the heater according to the comparison result.

In some embodiments, the method specifically includes: When the actual current value is greater than the target current value, increase the crystal pulling speed of the seed crystal pulling structure and/or the power of the heater; The crystal pulling speed of the pulling structure and/or the power of the heater.

When the actual current value is greater than the target current value, it means that the actual diameter is too large, which can be controlled by increasing the crystal pulling speed of the seed crystal pulling structure and/or the power of the heater to ensure that the actual diameter is close to or equal to the target diameter ; When the actual current value is less than the target current value, it means that the actual diameter is too small, which can be controlled by reducing the crystal pulling speed of the seed crystal pulling structure and/or the power of the heater to ensure that the actual diameter is close to the target diameter.

In this embodiment, a database of current-diameter changes in the finishing process can be established and obtained to realize automatic control of different finishing shape requirements; during the actual finishing process, the diameter of the ending is monitored according to the change of the actual current value to ensure that the finishing process is controllable. Improve the success rate of finishing; in addition, the diameter parameter at the time of finishing can be set in advance, and the relationship between the actual diameter and the set value can be compared in real time during the finishing process to control the finishing procedure in a loop, so as to achieve the purpose of automatic finishing, reduce personnel costs, and improve production capacity.

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

1: Power module 2: Seed crystal pulling structure 3: crystal 4: Graphite crucible 5: Quartz crucible 6: Silicon solution 7: Crucible shaft 301: thin neck 302: crystal shoulder 303: crystal body 304: crystal tail 101-103: Steps

FIG. 1 is a schematic structural view of a single crystal silicon pulling control device according to an embodiment of the present invention; Fig. 2 is a schematic diagram of the resistance value change during the finishing process of the crystal according to the embodiment of the present invention; FIG. 3 is a schematic flowchart of a control method for pulling single crystal silicon according to an embodiment of the present invention.

101-103: Steps

Claims (7)

A single crystal silicon crystal pulling control device is applied to a single crystal silicon crystal pulling furnace. The single crystal silicon crystal pulling furnace includes a furnace body. The furnace body is provided with a crucible and a heater. The crucible is connected to a crucible shaft. Based on the quartz crucible containing the silicon solution, the graphite crucible wrapped outside the quartz crucible, and the seed crystal pulling structure located above the graphite crucible, the single crystal silicon crystal pulling control device includes: A power module, one end of the power module is connected to the crucible shaft, and the other end is connected to the seed crystal pulling structure, which is used to provide electrical signals for the crystal fixed in the seed crystal pulling structure and the silicon in the quartz crucible When the solutions are in contact, a current loop is formed between the crucible shaft, the quartz crucible, the graphite crucible, the silicon solution, the crystal and the seed crystal pulling structure; The measurement module is used to measure the actual current value in the current loop in real time; The control module is used to determine the target current value according to the target diameter of the crystal tail, compare the actual current value with the target current value, and control the crystal pulling speed of the seed crystal pulling structure and/or the heater according to the comparison result power. The single crystal silicon pulling control device as described in Claim 1, wherein, The control module is specifically used to increase the crystal pulling speed of the seed crystal pulling structure and/or the power of the heater when the actual current value is greater than the target current value; when the actual current value is less than the target current value , reduce the crystal pulling speed of the seed crystal pulling structure and/or the power of the heater. The single crystal silicon pulling control device as described in Claim 1, wherein, The control module is also used to acquire multiple sets of measurement data, and fit the corresponding relationship between the target diameter and the target current value according to the multiple sets of measurement data, each set of measurement data includes at least the current value in the current loop, The diameter of the crystal tail and the varying length of the crystal tail. A single crystal silicon crystal pulling furnace, comprising a furnace body, the furnace body is provided with a crucible and a heater, the crucible is connected with a crucible shaft, and the crucible includes a quartz crucible for containing silicon solution and a graphite crucible wrapped outside the quartz crucible , and the seed crystal pulling structure located above the graphite crucible, further comprising the single crystal silicon crystal pulling control device as described in any one of Claims 1 to 3. A single crystal silicon crystal pulling control method, applied to a single crystal silicon crystal pulling furnace, the single crystal silicon crystal pulling furnace includes a furnace body, a crucible and a heater are arranged in the furnace body, the crucible is connected with a crucible shaft, and the crucible includes a Based on the quartz crucible containing the silicon solution, the graphite crucible wrapped outside the quartz crucible, and the seed crystal pulling structure located above the graphite crucible, the single crystal silicon pulling control method includes: Input electrical signals to the crucible shaft and the seed crystal pulling structure, so that when the crystal fixed by the seed crystal pulling structure is in contact with the silicon solution in the quartz crucible, the crucible shaft, the quartz crucible, the graphite crucible, A current loop is formed among the silicon solution, the crystal and the seed pulling structure; Instantly measure the actual current value in the current loop; Determine the target current value according to the target diameter of the crystal tail, compare the actual current value with the target current value, and control the crystal pulling speed of the seed crystal pulling structure and/or the power of the heater according to the comparison result. The single crystal silicon pulling control method as described in Claim 5, wherein the method specifically includes: When the actual current value is greater than the target current value, increase the crystal pulling speed of the seed crystal pulling structure and/or the power of the heater; The crystal pulling speed of the pulling structure and/or the power of the heater. The single crystal silicon pulling control method as described in Claim 5, wherein the method further includes: Obtain multiple sets of measurement data, and fit the corresponding relationship between the target diameter and the target current value according to the multiple sets of measurement data. Each set of measurement data includes at least the current value in the current loop, the diameter of the crystal tail and the crystal tail of varying lengths.

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