1. A method for monitoring the liquid level position of a melt is applied to a crystal pulling furnace with an L-shaped quartz column arranged at the bottom of a guide cylinder, wherein the bottom end of the quartz column is vertically downward and is vertical to the liquid level to be measured and is lower than the lowest point of the guide cylinder, and the method comprises the following steps:

after the liquid level to be measured is contacted with the bottom end of the quartz column for multiple times according to a set single descending distance from the contact of the liquid level to be measured and the bottom end of the quartz column, acquiring a corresponding relation between the distance between the liquid level to be measured and the bottom end of the quartz column and the distance between pixels of a bright ring formed by seed crystals on the liquid level to be measured;

in the growth process of the single crystal silicon rod, obtaining the actual measurement pixel distance between bright rings formed by the tail end of the single crystal silicon rod on the melt liquid level;

determining the measured distance between the melt liquid level and the bottom end of the quartz column based on the measured distance between the pixels and the corresponding relation;

and acquiring the actually measured position of the melt liquid level based on the actually measured distance and the distance between the bottom end of the quartz column and the lowest point of the guide cylinder.

2. The method as claimed in claim 1, wherein the obtaining of the correspondence between the distance between the liquid level to be measured and the bottom end of the quartz column and the distance between pixels between bright rings formed by the seed crystals on the liquid level to be measured after the liquid level to be measured is lowered for a plurality of times according to a set single lowering distance from the contact between the liquid level to be measured and the bottom end of the quartz column comprises:

descending the liquid level to be measured for multiple times according to the set single descending distance L1 from the contact of the liquid level to be measured and the bottom end of the quartz column, and obtaining the distance H between the liquid level to be measured and the bottom end of the quartz column after each descending_iWherein i is the number of drops;

after the liquid level to be detected descends each time, descending seed crystals are contacted with the liquid level to be detected, and obtaining the distance h between pixels between bright rings formed by the seed crystals on the liquid level to be detected_i；

According to the distance H between the liquid level to be detected and the bottom end of the quartz column after each descent_iAnd an inter-pixel distance h between the bright rings_iAnd acquiring a corresponding relation K between the distance H between the liquid level to be detected and the bottom end of the quartz column and the distance H between the pixels between the bright rings.

3. The method of claim 2, wherein the step of generating the second signal comprises generating a second signal based on the first signal and the second signalDescending the liquid level to be measured for multiple times according to the set single descending distance L1 from the contact of the liquid level to be measured and the bottom end of the quartz column, and obtaining the distance H between the liquid level to be measured and the bottom end of the quartz column after each descending_iThe method comprises the following steps:

when the liquid level to be detected is just contacted with the bottom end of the quartz column, setting the position of the liquid level to be detected as a zero position;

when the liquid level to be detected descends for i times, acquiring the distance H between the liquid level to be detected and the bottom end of the quartz column after each descent according to the descending time i of the liquid level to be detected and the set single descending distance L1_i＝i×L1。

4. The method as claimed in claim 2, wherein after each time the liquid level to be measured descends, the descending seed crystal is contacted with the liquid level to be measured, and the inter-pixel distance h between bright rings formed by the seed crystal on the liquid level to be measured is obtained_iThe method comprises the following steps:

after the liquid level to be measured descends by the set single descending distance L1 each time, descending seed crystals to contact with the liquid level to be measured, and collecting pixels of a bright ring formed on the liquid level to be measured by the seed crystals;

acquiring the central coordinate (x) of a fitting circle region corresponding to the bright ring according to the acquired pixels of the bright ring_i，y_i)；

According to the central coordinate (x) of the fitting circle area corresponding to the bright ring_i，y_i) Obtaining the distance between the pixels between the bright ringsWherein i is more than or equal to 1 and less than or equal to n.

5. The method according to claim 4, wherein the central coordinates (x) of the fitting circle region corresponding to the bright ring are obtained according to the collected pixels of the bright ring_i，y_i) The method comprises the following steps:

after the seed crystal forms the bright ring on the liquid level to be measured each time, collecting pixels of the bright ring by using an industrial camera;

fitting a circular area corresponding to the bright ring according to the collected pixels of the bright ring;

obtaining the central coordinate (x) of the circular area corresponding to the bright ring_i，y_i)。

6. The method according to claim 2, wherein the distance H between the liquid level to be measured and the bottom end of the quartz column after each descent is determined according to the measured liquid level_iAnd an inter-pixel distance h between the bright rings_iAnd acquiring the corresponding relation K between the distance H between the liquid level to be detected and the bottom end of the quartz column and the distance H between the pixels between the bright rings, wherein the corresponding relation K comprises the following steps:

after the liquid level to be measured descends n times in total, acquiring a corresponding relation K between a distance H between the liquid level to be measured and the bottom end of the quartz column and a distance H between pixels between the bright rings according to a formula (1):

wherein i is more than or equal to 1 and less than or equal to n.

7. The method of claim 1, wherein determining the measured distance of the melt level from the bottom end of the quartz column based on the measured inter-pixel distance and the correspondence comprises:

and obtaining the actually measured distance H 'between the melt liquid level and the bottom end of the quartz column according to the product of the actually measured distance H' between the pixels and the corresponding relation K.

8. A system for monitoring melt level position, the system comprising: a first acquisition section, a second acquisition section, a first determination section, and a third acquisition section; wherein the content of the first and second substances,

the first acquisition part is configured to acquire a corresponding relation between a distance between the liquid level to be detected and the bottom end of the quartz column and an inter-pixel distance between bright rings formed by seed crystals on the liquid level to be detected after the liquid level to be detected is lowered for multiple times according to a set single lowering distance from the liquid level to be detected to the bottom end of the quartz column after the liquid level to be detected is contacted with the bottom end of the quartz column;

the second acquiring part is configured to acquire an actually measured inter-pixel distance between bright rings formed by the tail end of the single crystal silicon rod on the liquid level of the melt during the growth process of the single crystal silicon rod;

the first determination part is configured to determine the measured distance between the melt liquid level and the bottom end of the quartz column based on the measured inter-pixel distance and the corresponding relation;

the third acquisition part is configured to acquire the measured position of the melt liquid level based on the distance between the measured distance and the bottom end of the quartz column and the lowest point of the guide cylinder.

9. A system for monitoring melt level position, the system comprising: the device comprises an L-shaped quartz column, an industrial camera, a lifting control device and a data processing device, wherein the L-shaped quartz column is arranged at the bottom of a guide cylinder in the crystal pulling furnace; wherein the content of the first and second substances,

the bottom end of the L-shaped quartz column is vertically downward vertical to the liquid level to be measured and is lower than the lowest point of the guide cylinder;

the industrial camera is used for collecting pixels of a bright ring formed by the seed crystal on the liquid level to be detected after the liquid level to be detected descends every time; collecting actual measurement pixels of a bright ring formed by the tail end of the single crystal silicon rod on the liquid level of the melt in the growth process of the single crystal silicon rod;

the lifting control device is used for controlling the quartz crucible to descend so as to ensure the set distance for each descending of the liquid level to be measured;

the data processing apparatus configured to: after the liquid level to be measured is contacted with the bottom end of the quartz column for multiple times according to a set single descending distance from the contact of the liquid level to be measured and the bottom end of the quartz column, acquiring a corresponding relation between the distance between the liquid level to be measured and the bottom end of the quartz column and the distance between pixels of a bright ring formed by seed crystals on the liquid level to be measured;

and acquiring the actual measurement pixel distance between bright rings formed by the tail end of the single crystal silicon rod on the melt liquid level in the growth process of the single crystal silicon rod;

determining the actually measured distance between the melt liquid level and the bottom end of the quartz column based on the actually measured distance between the pixels and the corresponding relation;

and acquiring the actually measured position of the melt liquid level based on the actually measured distance and the distance between the bottom end of the quartz column and the lowest point of the guide cylinder.

10. A computer storage medium having stored thereon a program for monitoring melt level position, the program being executable by at least one processor to perform the method steps of monitoring melt level position of any of claims 1 to 7.

Background

Single crystal silicon rods are mostly produced by the Czochralski (Czochralski) method, also referred to as the Czochralski method. The method uses the principle of condensation crystallization driving of melt, and at the interface of solid and liquid, the phase change from liquid to solid is generated due to the temperature drop of the melt. The silicon single crystal rod grown by the Czochralski method has high oxygen content and large diameter, and is a method widely adopted at present, however, as the silicon single crystal rod grows continuously, the volume of molten silicon in a crucible is gradually reduced, and the liquid level of the molten silicon is continuously reduced, so that the growth control and the crystal quality of the crystal are influenced. Therefore, the position of the melt liquid level in the quartz crucible needs to be monitored in real time in the preparation process of the single crystal silicon rod, so that the control of the melt liquid level position is in a closed-loop control state, and higher control precision can be obtained.

Because the temperature of the measured melt silicon is high, a non-contact measurement method is generally adopted, and the commonly adopted scheme comprises a thermal shield reflection method, namely, a Charge Coupled Device (CCD) camera is arranged on an observation window on a crystal pulling furnace, and the reflection of the lower edge of a thermal shield and the reflection of the thermal shield on the melt liquid level in the crystal pulling furnace are observed; and the image processing system scans the image shot by the CCD, calculates to obtain the radius of the inverted image of the heat shield on the liquid level of the melt, and substitutes the radius value into a deduced relation formula of the radius r of the inverted image of the heat shield and the relative height D of the liquid level to calculate the relative height of the liquid level of the melt. As can be seen from the above description: although the structure and the installation of the heat shield reflection method are simple, the edge of the bottom of the heat shield is a closed circle without special characteristic points, so that the position variation between the heat shield and the reflection thereof cannot be accurately measured, the sizes of the areas presented by the heat shield reflection on the liquid level are different due to the difference of the liquid level in the growth process of the silicon single crystal rod, and the coordinates and the variation of the heat shield reflection can also not be accurately measured.

Disclosure of Invention

In view of the foregoing, embodiments of the present invention are directed to a method, system, and computer storage medium for monitoring melt level position; the method can prepare the single crystal silicon rod with a central shaft, a seed crystal end cone and a tail end cone, and a cylinder with nearly constant diameter is arranged between the seed crystal end cone and the tail end cone of the single crystal silicon rod so as to improve the quality of the single crystal silicon rod.

The technical scheme of the embodiment of the invention is realized as follows:

in a first aspect, the embodiment of the invention provides a method for monitoring the liquid level position of a melt, which is applied to a crystal pulling furnace provided with an L-shaped quartz column at the bottom of a guide cylinder, wherein the bottom end of the quartz column is vertically downward perpendicular to the liquid level to be measured and is lower than the lowest point of the guide cylinder, and the method comprises the following steps:

after the liquid level to be measured is contacted with the bottom end of the quartz column for multiple times according to a set single descending distance from the contact of the liquid level to be measured and the bottom end of the quartz column, acquiring a corresponding relation between the distance between the liquid level to be measured and the bottom end of the quartz column and the distance between pixels of a bright ring formed by seed crystals on the liquid level to be measured;

in the growth process of the single crystal silicon rod, obtaining the actual measurement pixel distance between bright rings formed by the tail end of the single crystal silicon rod on the melt liquid level;

determining the measured distance between the melt liquid level and the bottom end of the quartz column based on the measured distance between the pixels and the corresponding relation;

and acquiring the actually measured position of the melt liquid level based on the actually measured distance and the distance between the bottom end of the quartz column and the lowest point of the guide cylinder.

In a second aspect, embodiments of the present invention provide a system for monitoring melt level position, the system comprising: a first acquisition section, a second acquisition section, a first determination section, and a third acquisition section; wherein the content of the first and second substances,

the first acquisition part is configured to acquire a corresponding relation between a distance between the liquid level to be detected and the bottom end of the quartz column and an inter-pixel distance between bright rings formed by seed crystals on the liquid level to be detected after the liquid level to be detected is lowered for multiple times according to a set single lowering distance from the liquid level to be detected to the bottom end of the quartz column after the liquid level to be detected is contacted with the bottom end of the quartz column;

the second acquiring part is configured to acquire an actually measured inter-pixel distance between bright rings formed by the tail end of the single crystal silicon rod on the liquid level of the melt during the growth process of the single crystal silicon rod;

the first determination part is configured to determine the measured distance between the melt liquid level and the bottom end of the quartz column based on the measured inter-pixel distance and the corresponding relation;

the third acquisition part is configured to acquire the measured position of the melt liquid level based on the distance between the measured distance and the bottom end of the quartz column and the lowest point of the guide cylinder.

In a third aspect, embodiments of the present invention provide a system for monitoring melt level position, the system comprising: the device comprises an L-shaped quartz column, an industrial camera, a lifting control device and a data processing device, wherein the L-shaped quartz column is arranged at the bottom of a guide cylinder in the crystal pulling furnace; wherein the content of the first and second substances,

the bottom end of the L-shaped quartz column is vertically downward vertical to the liquid level to be measured and is lower than the lowest point of the guide cylinder;

the industrial camera is used for collecting pixels of a bright ring formed by the seed crystal on the liquid level to be detected after the liquid level to be detected descends every time; collecting actual measurement pixels of a bright ring formed by the tail end of the single crystal silicon rod on the liquid level of the melt in the growth process of the single crystal silicon rod;

the lifting control device is used for controlling the quartz crucible to descend so as to ensure the set distance for each descending of the liquid level to be measured;

the data processing apparatus configured to: after the liquid level to be measured is contacted with the bottom end of the quartz column for multiple times according to a set single descending distance from the contact of the liquid level to be measured and the bottom end of the quartz column, acquiring a corresponding relation between the distance between the liquid level to be measured and the bottom end of the quartz column and the distance between pixels of a bright ring formed by seed crystals on the liquid level to be measured;

and acquiring the actual measurement pixel distance between bright rings formed by the tail end of the single crystal silicon rod on the melt liquid level in the growth process of the single crystal silicon rod;

determining the actually measured distance between the melt liquid level and the bottom end of the quartz column based on the actually measured distance between the pixels and the corresponding relation;

and acquiring the actually measured position of the melt liquid level based on the actually measured distance and the distance between the bottom end of the quartz column and the lowest point of the guide cylinder.

In a fourth aspect, embodiments of the present invention provide a computer storage medium storing a program for monitoring melt level position, the program being executed by at least one processor to implement the method steps for monitoring melt level position of the first aspect.

The embodiment of the invention provides a method and a system for monitoring the liquid level position of a melt and a computer storage medium; obtaining a corresponding relation between a pixel distance between bright rings formed by seed crystals on a liquid level to be measured and a distance between the liquid level to be measured and the bottom end of a quartz column in advance, and then obtaining an actually measured distance between a melt liquid level and the bottom end of the quartz column according to an actually measured pixel distance between the bright rings formed by the tail end of the monocrystalline silicon rod on the melt liquid level and the corresponding relation when the position of the melt liquid level is actually measured; therefore, the distance between the melt liquid level and the bottom of the guide cylinder can be accurately measured under the condition of non-contact with the melt liquid level, and the closed-loop control of the growth process of the silicon single crystal rod is realized.

Drawings

FIG. 1 is a schematic view of a crystal pulling furnace according to an embodiment of the present invention.

Fig. 2 is a schematic flow chart of a method for monitoring a melt level according to an embodiment of the present invention.

Fig. 3 is a schematic view of a bright ring formed on a liquid level to be measured by the seed crystal according to the embodiment of the present invention.

FIG. 4 is a schematic diagram illustrating a relationship between a distance between a liquid level and a bottom end of a quartz column and a distance between pixels according to an embodiment of the present invention.

Fig. 5 is a schematic diagram of a system for monitoring a melt level according to an embodiment of the present invention.

Fig. 6 is a schematic diagram of a hardware component structure according to an embodiment of the present invention.

Detailed Description

The technical solution in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention.

Referring to fig. 1, which shows a crystal pulling furnace device 10 capable of implementing the technical solution of the embodiment of the invention, as shown in fig. 1, in the crystal pulling furnace device 10, an L-shaped quartz column 102 is arranged at the bottom of a guide cylinder 101, wherein a bottom end 1021 of the quartz column 102 is vertically downward perpendicular to a liquid level 103 to be measured and is lower than the lowest point of the guide cylinder 101, and when the quartz column 102 is installed, as shown in fig. 1, the distance between the bottom end 1021 of the quartz column 102 and the lowest point of the guide cylinder 101 is L0. When the crystal pulling furnace device 10 is used for pulling the silicon single crystal rod, the seed crystal 104 is descended to be in contact with the liquid level 103 to be measured, and a bright ring is formed on the surface of the liquid level 103 to be measured, and can be observed in real time through the observation window 105. The crystal pulling furnace apparatus 10 further comprises a lifting control device 108 connected with the quartz crucible 107, and the lifting control device 108 can be a crucible lifting mechanism which is mainly used for controlling the lifting of the quartz crucible 107 so as to enable the liquid level 103 to be measured to descend or ascend in the process of pulling the monocrystalline silicon rod. It is understood that in an actual crystal puller installation, the crystal puller installation 10 shown in FIG. 1 may also include other structures not shown in FIG. 1, and embodiments of the present invention are not described in detail.

Referring to fig. 2, a method for monitoring the melt level position is provided based on a crystal pulling furnace apparatus 10, and the method is applied to the crystal pulling furnace apparatus 10 shown in fig. 1 for preparing a single crystal silicon rod, and comprises the following steps:

s201, after the liquid level to be detected is contacted with the bottom end of the quartz column, the liquid level to be detected is lowered for multiple times according to a set single lowering distance, and then the corresponding relation between the distance between the liquid level to be detected and the bottom end of the quartz column and the distance between pixels of a bright ring formed by seed crystals on the liquid level to be detected is obtained;

s202, acquiring an actually measured inter-pixel distance between bright rings formed by the tail end of the single crystal silicon rod on the melt liquid level in the growth process of the single crystal silicon rod;

s203, determining the actually measured distance between the melt liquid level and the bottom end of the quartz column based on the actually measured distance between the pixels and the corresponding relation;

and S204, acquiring the actually measured position of the melt liquid level based on the actually measured distance and the distance between the bottom end of the quartz column and the lowest point of the guide cylinder.

For the technical solution shown in fig. 2, it should be noted that, as shown in fig. 3, the CCD camera 106 disposed in the observation window 105 is used for observing a bright ring formed by the seed crystal 104 on the liquid level 103 to be measured in the specific implementation process; the CCD camera 106 can clearly adjust the quartz column 102, the end of the seed crystal 104, and the liquid level 103 to be measured to the visual field.

In addition, in the implementation process, as shown in fig. 1, a data processing device 109 capable of performing data processing may be connected to the CCD camera 106, so that steps or tasks other than pixel acquisition and control of the lifting and lowering of the quartz crucible 107 in the technical solution shown in fig. 2 can be performed by the data processing device 109.

With regard to the above technical solution, step S201 may be regarded as a process of generating the corresponding relationship K by testing in advance before actually measuring the distance between the melt level and the bottom end of the quartz column. The accuracy of the correspondence relationship K depends not only on the number of times the liquid level 103 to be measured is lowered but also on the distance L1 set for each lowering. Step S202, step S203, and step S204 may be regarded as a process of actually measuring the distance between the melt level and the bottom of the draft tube, and thus, the accuracy in the actual measurement process may be controlled by controlling the accuracy of generating the correspondence K.

For the technical solution shown in fig. 2, in some possible implementation manners, after the liquid level to be measured is lowered for multiple times from the contact between the liquid level to be measured and the bottom end of the quartz column according to a set single lowering distance, obtaining a correspondence between a distance between the liquid level to be measured and the bottom end of the quartz column and an inter-pixel distance between bright rings formed by seed crystals on the liquid level to be measured includes:

descending the liquid level to be measured and the bottom end of the quartz column for multiple times according to the set single descending distance L1 from the contact of the liquid level to be measured and the bottom end of the quartz columnA liquid level, and obtaining the distance H between the liquid level to be measured and the bottom end of the quartz column after each descent_iWherein i is the number of drops;

after the liquid level to be detected descends each time, descending seed crystals are contacted with the liquid level to be detected, and obtaining the distance h between pixels between bright rings formed by the seed crystals on the liquid level to be detected_i；

According to the distance H between the liquid level to be detected and the bottom end of the quartz column after each descent_iAnd an inter-pixel distance h between the bright rings_iAnd acquiring a corresponding relation K between the distance H between the liquid level to be detected and the bottom end of the quartz column and the distance H between the pixels between the bright rings.

For the above specific implementation manner, in some examples, the liquid level to be measured is lowered for multiple times according to the set single lowering distance L1 from the time when the liquid level to be measured contacts the bottom end of the quartz column, and the distance H between the liquid level to be measured and the bottom end of the quartz column is obtained after each lowering_iThe method comprises the following steps:

when the liquid level to be detected is just contacted with the bottom end of the quartz column, setting the position of the liquid level to be detected as a zero position;

when the liquid level to be detected descends for i times, acquiring the distance H between the liquid level to be detected and the bottom end of the quartz column after each descent according to the descending time i of the liquid level to be detected and the set single descending distance L1_i＝i×L1。

Specifically, since step S201 is considered as a process of a preliminary test to generate the correspondence relationship, in the preliminary test process, the liquid level 103 to be measured for the preliminary test may be held in the quartz crucible 107, and the quartz crucible 107 is first moved in the vertical direction by the elevation control device 108 until the liquid level 103 to be measured comes into contact with the bottom end 1021 of the quartz column 102, at which time the distance between the liquid level 103 to be measured and the bottom end 1021 of the quartz column 102 is 0; subsequently, the quartz crucible 107 is controlled to descend by the elevation control device 108 a plurality of times each time according to the set single descending distance L1, such as 2mm, and thus, the distance between the liquid level 103 to be measured and the bottom end 1021 of the quartz column 102 after each descending is obtained2 x i mm, wherein i represents the current descending times, therefore, the distance H between the liquid level 103 to be measured and the bottom end 1021 of the quartz column 102 after each descending_i＝i×L1。

For the above specific implementation manner, in some examples, after the liquid level to be measured descends each time, the descending seed crystal contacts the liquid level to be measured, and the inter-pixel distance h between bright rings formed by the seed crystal on the liquid level to be measured is obtained_iThe method comprises the following steps:

after the liquid level to be measured descends by the set single descending distance L1 each time, descending seed crystals to contact with the liquid level to be measured, and collecting pixels of a bright ring formed on the liquid level to be measured by the seed crystals;

acquiring the central coordinate (x) of a fitting circle region corresponding to the bright ring according to the acquired pixels of the bright ring_i，y_i)；

According to the central coordinate (x) of the fitting circle area corresponding to the bright ring_i，y_i) Obtaining the distance between the pixels between the bright ringsWherein i is more than or equal to 1 and less than or equal to n.

For the foregoing specific implementation manner, in some examples, the center coordinates (x) of the fitting circle region corresponding to the bright ring are obtained according to the collected pixels of the bright ring_i，y_i) The method comprises the following steps:

after the seed crystal forms the bright ring on the liquid level to be measured each time, collecting pixels of the bright ring by using an industrial camera;

fitting a circular area corresponding to the bright ring according to the collected pixels of the bright ring;

obtaining the central coordinate (x) of the circular area corresponding to the bright ring_i，y_i)。

As can be understood, referring to fig. 3, when the liquid level 103 to be measured is lowered, the seed crystal 104 is lowered to contact the liquid level 103 to be measured, and the bright ring formed by the seed crystal 104 on the liquid level 103 to be measured can be approximately regarded as a circular area (an oval shape is shown in the figure). Thus, according to the CCD camera 106The edge of the bright ring fitting circular pixel is extracted by a Sobel algorithm, and the center coordinate (x) of the bright ring is obtained by Hough transformation and fitting_i，y_i) (ii) a When the liquid level 103 to be measured descends each time, bright rings are formed when the seed crystal 104 contacts the liquid level 103 to be measured, the central coordinates of fitting circle areas of the bright rings can be obtained, and the inter-pixel distance h between the bright rings formed by the seed crystal 104 on the liquid level 103 to be measured can be obtained according to the central coordinates of the fitting circle areas_i. For example, when the liquid level 103 is dropped by 2mm for the first time, the center coordinate of the fitting circle region of the bright ring formed on the liquid level 103 by the seed crystal 104 is (x)₁，y₁) Correspondingly, the liquid level 103 is lowered by 2mm again, and the center coordinate of the fitting circle area of the bright ring formed by the seed crystal 104 on the liquid level 103 is (x)₂，y₂) After the two central coordinates are obtained, the inter-pixel distance of the two central coordinates can be calculatedAt this time, the bottom 1021 of the quartz column 102 is used as a reference, and the position of the liquid level 103 to be measured is H₂＝2×2mm。

Corresponding to the foregoing implementation, in detail, the quartz crucible 107 is first moved by the lifting control device 108 in the vertical direction until the liquid level 103 to be measured contacts the bottom end 1021 of the quartz column 102, and at this time, the distance between the bottom end 1021 of the quartz column 102 and the liquid level 103 to be measured is 0; next, the quartz crucible 107 is controlled to descend by the elevation control device 108 a plurality of times each time according to the set single descent distance L1, for example, 2mm, so that after each descent, the inter-pixel distance h corresponding to the current descent number can be obtained by the above-described exemplary contents based on the test pixel photographed by the CCD camera_iWhere i represents the current number of drops.

For the above specific implementation manner, in some examples, the distance H between the liquid level to be measured and the bottom end of the quartz column after each descent is determined according to the reference_iAnd an inter-pixel distance h between the bright rings_iObtaining the liquid level to be measured and the bottom end of the quartz columnThe correspondence K between the distance H and the inter-pixel distance H between the bright rings includes:

after the liquid level to be measured descends n times in total, acquiring a corresponding relation K between a distance H between the liquid level to be measured and the bottom end of the quartz column and a distance H between pixels between the bright rings according to a formula (1):

wherein i is more than or equal to 1 and less than or equal to n.

Understandably, through the implementation manner, in the process of testing in advance to generate the corresponding relation K, the distance H between the liquid level 103 to be measured and the bottom end 1021 of the quartz column 102 after each descent is obtained_iAnd inter-pixel distance h_iSince the two distance values have a linear relationship, the distance H between the liquid level 103 to be measured and the bottom end 1021 of the quartz column 102 can be obtained according to the whole process after n times of descending_nAnd inter-pixel distance h_nThe linear relationship is fitted, as shown in fig. 4, so as to obtain a corresponding relationship K between the distance H between the liquid level 103 to be measured and the bottom end 1021 of the quartz column 102 and the distance H between the pixels.

For the technical solution shown in fig. 2, in some possible implementations, the determining the measured distance between the melt level and the bottom end of the quartz column based on the measured inter-pixel distance and the corresponding relationship includes:

and obtaining the actually measured distance H 'between the melt liquid level and the bottom end of the quartz column according to the product of the actually measured distance H' between the pixels and the corresponding relation K.

It should be noted that, with respect to the technical solution and the implementation manner thereof shown in fig. 2, through the correspondence K obtained in the preliminary testing process, in the actual measurement process of the growth of the single crystal silicon rod, based on the correspondence K obtained in advance and the actual measurement pixel distance H ' between the bright rings formed at the melt level by the tail end of the single crystal silicon rod obtained in the actual measurement, the actual measurement distance H ' between the melt level and the bottom end 1021 of the quartz column 102 can be obtained in real time as K × H '.

Thus, after the actual measurement distance H 'between the melt liquid level and the bottom end 1021 of the quartz column 102 is obtained, the distance H' + L0 between the melt liquid level and the lowest point of the guide cylinder 101 can be obtained, and the distance is fed back to the crystal pulling furnace device 10 to realize closed-loop control, which is beneficial to controlling the position of the melt liquid level in real time in the growth process of the silicon single crystal rod so as to improve the crystal forming rate and the production efficiency of the silicon single crystal growth.

Based on the same inventive concept of the foregoing technical solution, referring to fig. 5, a system 50 for monitoring the melt level position according to an embodiment of the present invention is shown, where the system 50 may include a first obtaining portion 501, a second obtaining portion 502, a first determining portion 503, and a third obtaining portion 504; wherein the content of the first and second substances,

the first obtaining part 501 is configured to obtain a correspondence relationship between a distance between the liquid level to be measured and the bottom end of the quartz column and an inter-pixel distance between bright rings formed by seed crystals on the liquid level to be measured after the liquid level to be measured is lowered for a plurality of times according to a set single lowering distance from the liquid level to be measured to the bottom end of the quartz column after the liquid level to be measured is brought into contact with the bottom end of the quartz column;

the second acquiring part 502 is configured to acquire an actually measured inter-pixel distance between bright rings formed on the melt liquid level at the tail end of the single crystal silicon rod during the growth of the single crystal silicon rod;

the first determining part 503 is configured to determine the measured distance between the melt level and the bottom end of the quartz column based on the measured inter-pixel distance and the corresponding relationship;

the third acquiring portion 504 is configured to acquire the measured position of the melt level based on the distance between the measured distance and the bottom end of the quartz column and the lowest point of the guide cylinder.

In the above scheme, the first acquisition section 501 is configured to:

descending the liquid level to be measured for multiple times according to the set single descending distance L1 from the contact of the liquid level to be measured and the bottom end of the quartz column, and obtaining the distance H between the liquid level to be measured and the bottom end of the quartz column after each descending_iWherein i is the number of drops;

after the liquid level to be detected descends each time, descending seed crystals are contacted with the liquid level to be detected, and obtaining the distance h between pixels between bright rings formed by the seed crystals on the liquid level to be detected_i；

According to the distance H between the liquid level to be detected and the bottom end of the quartz column after each descent_iAnd an inter-pixel distance h between the bright rings_iAnd acquiring a corresponding relation K between the distance H between the liquid level to be detected and the bottom end of the quartz column and the distance H between the pixels between the bright rings.

In the above scheme, the first acquisition section 501 is configured to:

when the liquid level to be detected is just contacted with the bottom end of the quartz column, setting the position of the liquid level to be detected as a zero position;

when the liquid level to be detected descends for i times, acquiring the distance H between the liquid level to be detected and the bottom end of the quartz column after each descent according to the descending time i of the liquid level to be detected and the set single descending distance L1_i＝i×L1。

In the above scheme, the first acquisition section 501 is configured to:

after the liquid level to be measured descends by the set single descending distance L1 each time, descending seed crystals to contact with the liquid level to be measured, and collecting pixels of a bright ring formed on the liquid level to be measured by the seed crystals;

acquiring the central coordinate (x) of a fitting circle region corresponding to the bright ring according to the acquired pixels of the bright ring_i，y_i)；

According to the central coordinate (x) of the fitting circle area corresponding to the bright ring_i，y_i) Obtaining the distance between the pixels between the bright ringsWherein i is more than or equal to 1 and less than or equal to n.

In the above scheme, the first acquisition section 501 is configured to:

after the seed crystal forms the bright ring on the liquid level to be measured each time, collecting pixels of the bright ring by using an industrial camera;

fitting a circular area corresponding to the bright ring according to the collected pixels of the bright ring;

obtaining the central coordinate (x) of the circular area corresponding to the bright ring_i，y_i)。

In the above scheme, the first obtaining portion 501 is further configured to:

and after the liquid level to be measured descends n times in total, acquiring a corresponding relation K between the distance H between the liquid level to be measured and the bottom end of the quartz column and the distance H between pixels between the bright rings according to the formula (1).

In the above scheme, the first determining section 503 is configured to:

and obtaining the actually measured distance H 'between the melt liquid level and the bottom end of the quartz column according to the product of the actually measured distance H' between the pixels and the corresponding relation K.

It is understood that in this embodiment, "part" may be part of a circuit, part of a processor, part of a program or software, etc., and may also be a unit, and may also be a module or a non-modular.

In addition, each component in the embodiment may be integrated in one processing unit, or each unit may exist alone physically, or two or more units are integrated in one unit. The integrated unit can be realized in a form of hardware or a form of a software functional module.

Based on the understanding that the technical solution of the present embodiment essentially or a part contributing to the prior art, or all or part of the technical solution may be embodied in the form of a software product stored in a storage medium, and include several instructions for causing a computer device (which may be a personal computer, a server, or a network device, etc.) or a processor (processor) to execute all or part of the steps of the method of the present embodiment. And the aforementioned storage medium includes: various media capable of storing program codes, such as a usb disk, a removable hard disk, a Read Only Memory (ROM), a Random Access Memory (RAM), a magnetic disk, or an optical disk.

Accordingly, the present embodiments provide a computer storage medium storing a program for monitoring melt level position, the program being executed by at least one processor to perform the method steps of monitoring melt level position as set forth in the above-described embodiments.

Based on the above system 50 for monitoring the melt level position in real time and the computer storage medium, referring to fig. 1, the hardware structure of the system 50 for monitoring the melt level position in real time is shown, which may include: the device comprises an L-shaped quartz column 102, an industrial camera 106, a lifting control device 108 and a data processing device 109, wherein the L-shaped quartz column 102 is arranged at the bottom of a guide cylinder 101 in the crystal pulling furnace; wherein the content of the first and second substances,

the bottom end 1021 of the L-shaped quartz column 102 is vertically downward and is vertical to the liquid level to be measured and is lower than the lowest point of the guide cylinder;

the industrial camera 106 is used for collecting pixels of a bright ring formed on the liquid level to be detected by the seed crystal after the liquid level to be detected descends every time; collecting actual measurement pixels of a bright ring formed by the tail end of the single crystal silicon rod on the liquid level of the melt in the growth process of the single crystal silicon rod;

the lifting control device 108 is used for controlling the quartz crucible to descend so as to ensure that the liquid level to be measured descends for a set distance each time;

the data processing apparatus 109 configured to: after the liquid level to be measured is contacted with the bottom end of the quartz column for multiple times according to a set single descending distance from the contact of the liquid level to be measured and the bottom end of the quartz column, acquiring a corresponding relation between the distance between the liquid level to be measured and the bottom end of the quartz column and the distance between pixels of a bright ring formed by seed crystals on the liquid level to be measured;

and acquiring the actual measurement pixel distance between bright rings formed by the tail end of the single crystal silicon rod on the melt liquid level in the growth process of the single crystal silicon rod;

determining the actually measured distance between the melt liquid level and the bottom end of the quartz column based on the actually measured distance between the pixels and the corresponding relation;

and acquiring the actually measured position of the melt liquid level based on the actually measured distance and the distance between the bottom end of the quartz column and the lowest point of the guide cylinder.

Specifically, the data processing device 109 may be a wireless device, a mobile or cellular phone (including a so-called smart phone), a Personal Digital Assistant (PDA), a video game console (including a video display, a mobile video game device, a mobile video conference unit), a laptop computer, a desktop computer, a television set-top box, a tablet computing device, an e-book reader, a setting or mobile media player, etc., and its specific hardware structure may be as shown in fig. 6, including: a communication interface 601, a memory 602, and a processor 603; the various components are coupled together by a bus system 604. It is understood that the bus system 604 is used to enable communications among the components. The bus system 604 includes a power bus, a control bus, and a status signal bus in addition to a data bus. For clarity of illustration, however, the various buses are labeled as bus system 604 in fig. 6. Wherein the content of the first and second substances,

the communication interface 601 is configured to receive and transmit signals during information transmission and reception with other external network elements;

the memory 602 is used for storing a computer program capable of running on the processor 603;

the processor 603 is configured to execute the functions and steps of configuring each component in the data processing apparatus 109 when running the computer program.

It will be appreciated that the memory 602 in embodiments of the invention may be either volatile memory or nonvolatile memory, or may include both volatile and nonvolatile memory. The non-volatile Memory may be a Read-Only Memory (ROM), a Programmable ROM (PROM), an Erasable PROM (EPROM), an Electrically Erasable PROM (EEPROM), or a flash Memory. Volatile Memory can be Random Access Memory (RAM), which acts as external cache Memory. By way of illustration and not limitation, many forms of RAM are available, such as Static random access memory (Static RAM, SRAM), Dynamic Random Access Memory (DRAM), Synchronous Dynamic random access memory (Synchronous DRAM, SDRAM), Double Data Rate Synchronous Dynamic Random Access Memory (DDRSDRAM), Enhanced Synchronous SDRAM (ESDRAM), Sync Link DRAM (SLDRAM), and Direct Rambus RAM (DRRAM). The memory 602 of the systems and methods described herein is intended to comprise, without being limited to, these and any other suitable types of memory.

And the processor 603 may be an integrated circuit chip having signal processing capabilities. In implementation, the steps of the above method may be performed by integrated logic circuits of hardware or instructions in the form of software in the processor 603. The Processor 603 may be a general purpose Processor, a Digital Signal Processor (DSP), an Application Specific Integrated Circuit (ASIC), a Field Programmable Gate Array (FPGA) or other Programmable logic device, discrete Gate or transistor logic device, discrete hardware component. The various methods, steps and logic blocks disclosed in the embodiments of the present invention may be implemented or performed. A general purpose processor may be a microprocessor or the processor may be any conventional processor or the like. The steps of the method disclosed in connection with the embodiments of the present invention may be directly implemented by a hardware decoding processor, or implemented by a combination of hardware and software modules in the decoding processor. The software module may be located in ram, flash memory, rom, prom, or eprom, registers, etc. storage media as is well known in the art. The storage medium is located in the memory 602, and the processor 603 reads the information in the memory 602, and performs the steps of the above method in combination with the hardware thereof.

It is to be understood that the embodiments described herein may be implemented in hardware, software, firmware, middleware, microcode, or any combination thereof. For a hardware implementation, the Processing units may be implemented within one or more Application Specific Integrated Circuits (ASICs), Digital Signal Processors (DSPs), Digital Signal Processing Devices (DSPDs), Programmable Logic Devices (PLDs), Field Programmable Gate Arrays (FPGAs), general purpose processors, controllers, micro-controllers, microprocessors, other electronic units configured to perform the functions described herein, or a combination thereof.

For a software implementation, the techniques described herein may be implemented with modules (e.g., procedures, functions, and so on) that perform the functions described herein. The software codes may be stored in a memory and executed by a processor. The memory may be implemented within the processor or external to the processor.

It should be noted that: the technical schemes described in the embodiments of the present invention can be combined arbitrarily without conflict.

The above description is only for the specific embodiments of the present invention, but the scope of the present invention is not limited thereto, and any person skilled in the art can easily conceive of the changes or substitutions within the technical scope of the present invention, and all the changes or substitutions should be covered within the scope of the present invention. Therefore, the protection scope of the present invention shall be subject to the protection scope of the appended claims.