CN216473570U - Positioning pin for measuring liquid level position of molten silicon and crystal silicon smelting furnace - Google Patents
Positioning pin for measuring liquid level position of molten silicon and crystal silicon smelting furnace Download PDFInfo
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- CN216473570U CN216473570U CN202120221631.1U CN202120221631U CN216473570U CN 216473570 U CN216473570 U CN 216473570U CN 202120221631 U CN202120221631 U CN 202120221631U CN 216473570 U CN216473570 U CN 216473570U
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Abstract
The utility model provides a measure locating pin and crystal silicon smelting pot that melts silicon liquid level position, the locating pin that measures melts silicon liquid level position includes: the first rod comprises a first part and a second part which are bent oppositely, the first part and the second part are both rod body structures, the second part comprises a first end and a second end which are opposite, and the first part is connected with the first end of the second part; the second rod is of a rod body structure and comprises a third end and a fourth end which are opposite, the third end is connected to the second end of the second part, and the second rod and the second part are coaxially arranged; wherein at least one of the second portion and the second rod is provided with a light-tight object inside the rod body. The positioning pin for measuring the liquid level position of the molten silicon and the crystalline silicon smelting furnace can improve the accuracy of Melt Gap measurement.
Description
Technical Field
The disclosure relates to the technical field of monocrystalline silicon growth, in particular to a positioning pin for measuring the position of a molten silicon liquid level and a crystalline silicon smelting furnace.
Background
Currently, Czochralski (Czochralski) is commonly used for producing monocrystalline silicon crystal rods, wherein a quartz crucible is used in a monocrystalline furnace for containing polycrystalline silicon raw materials, the polycrystalline silicon raw materials are melted by heating the crucible, a guide cylinder is arranged above the crucible in the monocrystalline furnace, and in the Czochralski monocrystalline silicon growth process, argon gas is usually continuously filled from the guide cylinder, flows through a gap between the liquid level of the molten silicon in the crucible and the guide cylinder, and is finally discharged from an exhaust port of a thermal field under the action of a vacuum pump.
With the continuous improvement of the quality requirement of silicon wafer materials, crystal defects in a crystal bar need to be well controlled in addition to controlling the resistivity and the oxygen content during the crystal pulling process, so that the crystal pulling process parameters need to be continuously optimized. The measurement of some crystal pulling process parameters is required to be more accurate, wherein an important parameter is Melt Gap, namely a Gap between the liquid level of the molten silicon and the guide cylinder, the measurement and control of the Melt Gap are important parameter indexes in a crystal pulling process, and the size of the Melt Gap has great influence on factors related to the growth and quality of the single crystal, such as the flowing of argon, the evaporation of impurities, the rotation stability of a silicon rod, the oxygen content of the silicon rod and the like. The Melt Gap is the distance from the bottom of the guide shell to the liquid level of the molten silicon in the crucible, the Melt Gap is measured after the melting is finished, and the Melt Gap is adjusted to a set value by adjusting the position of the liquid level. In the subsequent crystal bar pulling process, the solution is continuously reduced in the pulling process, the liquid level is continuously reduced, and meanwhile, the crucible is continuously raised, so that the Melt Gap is required to be monitored in real time and accurately adjusted.
Generally, the measuring and monitoring method is to insert a positioning pin at the bottom of the guide shell, and the measuring is carried out by the inverted image imaging principle of the positioning pin on the liquid level of the molten silicon. In the related art, a quartz positioning pin is usually used and is transparent, and in the actual liquid level detection process, the inverted image of the quartz positioning pin in the solution is very fuzzy, so that the accuracy of liquid level monitoring is influenced.
SUMMERY OF THE UTILITY MODEL
The utility model aims to provide a measure locating pin and crystal silicon smelting pot that melts silicon liquid level position can improve Melt Gap and measure the accuracy.
The technical scheme provided by the disclosure is as follows:
the embodiment of the present disclosure provides a positioning pin for measuring a liquid level position of molten silicon, including:
the first rod comprises a first part and a second part which are oppositely bent, the first part and the second part are both rod body structures, the second part comprises a first end and a second end which are opposite, and the first part is connected with the first end of the second part;
the second rod is of a rod body structure and comprises a third end and a fourth end which are opposite, the third end is connected to the second end of the second part, and the second rod and the second part are coaxially arranged;
wherein at least one of the second portion and the second rod is provided with a light-tight object inside the rod body.
For example, a first groove is formed in the second end face of the second portion, and the opaque object is accommodated in the first groove.
Illustratively, a second groove is arranged on the end face of the third end of the second rod, and the opaque object is accommodated in the second groove.
Illustratively, the second end of the second portion is connected to the third end of the second rod by welding.
Illustratively, the cross-sectional shape of the first portion in a direction perpendicular to the axis of the first portion is quadrilateral.
Illustratively, at least one diagonal of the polygon is parallel to the axis of the second portion.
Illustratively, the cross-sectional shape of the second portion in a direction perpendicular to the axis of the second portion is polygonal.
Illustratively, the outer peripheral surface of the second portion includes a plurality of side surfaces, each of the side surfaces corresponding to a side of the polygon, wherein the first portion is connected to a first side surface of the plurality of side surfaces, and the first side surface is perpendicular to an axis of the first portion.
Illustratively, the opaque object comprises a graphite material.
The embodiment of the disclosure also provides a crystal silicon melting furnace, which comprises a guide cylinder, wherein the guide cylinder comprises a top opening and a bottom opening; the positioning pin for measuring the liquid level position of the molten silicon is detachably mounted at the bottom position of the guide shell, a mounting hole is formed in the bottom opening position of the guide shell, and the first part is inserted into the mounting hole.
The beneficial effects brought by the present disclosure are as follows:
the utility model provides a measure locating pin of fused silicon liquid level position for measure Melt Gap at the crystal pulling in-process, the clearance between fused silicon liquid level and the draft tube promptly, the locating pin of measuring fused silicon liquid level position is a combined lifting hook, including first pole and second pole, the second part and the coaxial setting of second pole of first pole, when actual measurement, the first part of first pole transversely inserts in the mounting hole of draft tube, second part and second pole are vertical downwards, through the inside light proof thing that sets up of the body of rod of at least one in second part and second pole, can form clear reflection at the Melt face of face, and then can accurately measure the position of fused silicon liquid level.
Drawings
Fig. 1 is a schematic structural diagram of a crystalline silicon furnace according to an embodiment of the present disclosure;
FIG. 2 is a schematic structural view of a positioning pin for measuring a position of a molten silicon surface according to some embodiments of the present disclosure;
FIG. 3 is an exploded view of a locating pin for measuring a position of a molten silicon surface according to other embodiments of the present disclosure.
Detailed Description
In order to make the objects, technical solutions and advantages of the embodiments of the present disclosure more apparent, the technical solutions of the embodiments of the present disclosure will be described clearly and completely with reference to the drawings of the embodiments of the present disclosure. It is to be understood that the described embodiments are only a few embodiments of the present disclosure, and not all embodiments. All other embodiments, which can be derived by a person skilled in the art from the described embodiments of the disclosure without any inventive step, are within the scope of protection of the disclosure.
Unless otherwise defined, technical or scientific terms used herein shall have the ordinary meaning as understood by one of ordinary skill in the art to which this disclosure belongs. The use of "first," "second," and similar terms in this disclosure is not intended to indicate any order, quantity, or importance, but rather is used to distinguish one element from another. Also, the use of the terms "a," "an," or "the" and similar referents do not denote a limitation of quantity, but rather denote the presence of at least one. The word "comprising" or "comprises", and the like, means that the element or item listed before the word covers the element or item listed after the word and its equivalents, but does not exclude other elements or items. The terms "connected" or "coupled" and the like are not restricted to physical or mechanical connections, but may include electrical connections, whether direct or indirect. "upper", "lower", "left", "right", and the like are used merely to indicate relative positional relationships, and when the absolute position of the object being described is changed, the relative positional relationships may also be changed accordingly.
Before describing in detail the positioning pin for measuring the position of the liquid level of molten silicon provided in the present disclosure, it is necessary to describe the following with respect to the related art:
in the related art, Melt Gap, i.e., the Gap between the surface of the molten silicon and the guide shell, is an important parameter index in the crystal pulling process, and the Melt Gap is required to be monitored in real time and accurately adjusted. The Melt Gap measuring and monitoring method is that a quartz lifting hook is inserted into the lower part of the guide cylinder, and the measurement is carried out by the reflection imaging principle of the quartz lifting hook on the liquid level of the molten silicon. Wherein, a lateral wall position for carrying out fused silicon liquid level measuring quartz lifting hook installs at interior draft tube, quartz hook is the L type, including first portion and second portion, there is the mounting hole on the draft tube inner wall, transversely put this quartz lifting hook's first portion in the mounting hole, then put the hand, under the action of gravity, its second portion can vertical part can be downward, through the lift graphite crucible, can make fused silicon liquid level and vertical part's second portion lower edge just contact, need accurately measure fused silicon liquid level position at the crystal pulling in-process, guarantee that the distance of draft tube and liquid level keeps the setting value, Melt Gap measurement process utilizes the inverted image formation of lifting hook in solution to go on. The quartz lifting hook adopted at present is transparent, and the accuracy of liquid level monitoring can be influenced in the actual liquid level detection process due to the fact that the inverted image of the quartz lifting hook in a solution is very fuzzy.
To solve the technical problem, the embodiment of the present disclosure provides a positioning pin for measuring a liquid level position of molten silicon and a crystalline silicon melting furnace, which can improve Melt Gap measurement accuracy.
As shown in fig. 1 to 2, an embodiment of the present disclosure provides a positioning pin for measuring a position of a liquid level of molten silicon, including: the first rod 100, the first rod 100 includes a first portion 110 and a second portion 120 which are oppositely bent, the first portion 110 and the second portion 120 are both rod body structures, the second portion 120 includes a first end and a second end which are opposite, and the first portion 110 is connected to the first end of the second portion 120; a second rod 200, wherein the second rod 200 is a rod body structure, the second rod 200 comprises a third end and a fourth end which are opposite to each other, the third end is connected to the second end of the second part 120, and the second rod 200 and the second part 120 are coaxially arranged; wherein at least one of said second portion 120 and said second rod 200 is provided with a non-light-transmitting object 300 inside the rod body.
The positioning pin for measuring the molten silicon liquid level position is used for measuring Melt Gap in the crystal pulling process, namely the Gap between the molten silicon liquid level and the guide shell 10, the positioning pin for measuring the molten silicon liquid level position is a combined type lifting hook and comprises a first rod 100 and a second rod 200, a second part 120 of the first rod 100 and the second rod 200 are coaxially arranged, during actual measurement, a first part 110 of the first rod 100 is transversely inserted into a mounting hole of the guide shell 10, the second part 120 and the second rod 200 are vertically downward, and a light-tight object 300 is arranged inside at least one rod body of the second part 120 and the second rod 200, so that a clear reflection can be formed on the molten liquid level 20, and the position of the molten silicon liquid level 20 can be accurately measured.
In some exemplary embodiments, as shown in fig. 2, a first groove 121 is disposed on the second end surface of the second portion 120, and the light-impermeable object 300 is disposed in the first groove 121.
In other exemplary embodiments, a second groove (not shown) is formed on the third end surface of the second rod 200, and the light-impermeable object 300 is accommodated in the second groove.
In the above solution, a first groove 121 may be disposed on a second end surface of the second portion 120, that is, an end surface of the first rod 100 for connecting with the second rod 200, and the first groove 121 is filled with the light-proof substance 300; it is also possible to provide a second groove on the end surface of the third end of the second rod 200, i.e. the end surface of the second rod 200 used for connecting with the first rod 100, and fill the second groove with a light-proof material 300, so as to realize that at least a part of the vertically downward portion of the positioning pin capable of showing a reflection on the liquid surface is light-proof, thereby showing a clear reflection on the liquid surface.
It should be noted that, in the above embodiment, the rod bodies of the first rod 100 and the second rod 200 may be made of quartz material.
Further, in some exemplary embodiments, the second end of the second portion 120 is welded to the third end of the second rod 200. Thus, the center of the second end surface of the second portion 120 may be provided with a first groove 121, or the center of the third end surface of the second rod 200 may be provided with a second groove, and then the second portion 120 and the second rod 200 are welded around the grooves by using a welding method.
Further, in an exemplary embodiment, as shown in fig. 3, the cross-sectional shape of the first portion 110 in a direction perpendicular to the axis of the first portion 110 is a quadrilateral.
With the above scheme, the cross section of the first portion 110 is a quadrangle, and in other embodiments, the cross section of the first portion 110 may also be another polygon, for example, a triangle or a pentagon.
Further, in an exemplary embodiment, at least one diagonal of the polygon is parallel to the axis of the second portion 120.
By adopting the scheme, at least one diagonal line in the first part 110 is parallel to the axis of the second part 120, so that when the first part 110 of the combined hook is inserted into the mounting hole of the guide shell 10, the second part 120 and the second rod 200 are in a vertical state under the action of gravity, and one diagonal line of the cross section of the first part 110 is parallel to the second part 120, namely one diagonal line of the cross section of the first part 110 is in a vertical state, so that the first part 110 of the first rod 100 of the combined hook can be further ensured to be inserted into the bottom of the guide shell 10, the second part 120 and the second rod 200 are ensured to be always kept in a vertical position, and the rotation is not easy to occur.
Further, in an exemplary embodiment, a cross-sectional shape of the second portion 120 in a direction perpendicular to an axis of the second portion 120 is a polygon, and an outer circumferential surface of the second portion 120 includes a plurality of side surfaces, each of the side surfaces corresponding to a side of the polygon, wherein the first portion 110 is connected to a first side surface of the plurality of side surfaces, and the first side surface is perpendicular to the axis of the first portion 110.
With the above-mentioned solution, the cross-sections of the first portion 110 and the second portion 120 are both polygonal, the manufacturing process of the first rod 100 is relatively simple, and on the other hand, the first side surface of the second portion 120 is perpendicular to the axis of the first portion 110, so that after the first portion 110 is transversely inserted into the mounting hole of the guide shell 10, the first side surface of the second portion 120 maintains a state of being perpendicular to the horizontal plane.
It is understood that, in practical applications, the second portion 120 may be a rod-shaped structure with other shapes, which is not limited to this.
In addition, as shown in fig. 1, an embodiment of the present disclosure further provides a crystalline silicon melting furnace, including a draft tube 10, where the draft tube 10 includes a top opening and a bottom opening; the positioning pin for measuring the liquid level position of the molten silicon provided by the embodiment of the present disclosure is detachably mounted at the bottom position of the draft tube 10, wherein a mounting hole is formed at the bottom opening position of the draft tube 10, and the first portion 110 is inserted into the mounting hole.
In some embodiments, a cross-sectional shape of the first portion 110 in a direction perpendicular to an axis of the first portion 110 is a polygon, and the mounting hole is a polygonal hole having the same shape as the cross-sectional shape of the first portion 110.
Obviously, the crystalline silicon melting furnace provided by the embodiment of the disclosure also has the technical effects brought by the positioning pin for measuring the liquid level position of the molten silicon provided by the embodiment of the disclosure, and details are not repeated herein.
The following points need to be explained:
(1) the drawings of the embodiments of the disclosure only relate to the structures related to the embodiments of the disclosure, and other structures can refer to the common design.
(2) For purposes of clarity, the thickness of layers or regions in the figures used to describe embodiments of the present disclosure are exaggerated or reduced, i.e., the figures are not drawn on a true scale. It will be understood that when an element such as a layer, film, region, or substrate is referred to as being "on" or "under" another element, it can be "directly on" or "under" the other element or intervening elements may be present.
(3) Without conflict, embodiments of the present disclosure and features of the embodiments may be combined with each other to arrive at new embodiments.
The above is only a specific embodiment of the present disclosure, but the scope of the present disclosure is not limited thereto, and the scope of the present disclosure should be determined by the scope of the claims.
Claims (10)
1. A positioning pin for measuring a position of a surface of molten silicon, comprising:
the first rod comprises a first part and a second part which are bent oppositely, the first part and the second part are both rod body structures, the second part comprises a first end and a second end which are opposite, and the first part is connected with the first end of the second part;
the second rod is of a rod body structure and comprises a third end and a fourth end which are opposite, the third end is connected to the second end of the second part, and the second rod and the second part are coaxially arranged;
wherein at least one of the second portion and the second rod is provided with a light-tight object inside the rod body.
2. The positioning pin for measuring the position of the surface of the molten silicon according to claim 1, wherein a first recess is provided in the second end surface of the second portion, and the opaque member is accommodated in the first recess.
3. The positioning pin for measuring the position of the surface of molten silicon according to claim 1, wherein a second recess is provided in the end face of the third end of the second rod, and the opaque member is accommodated in the second recess.
4. The positioning pin for measuring a position of a surface of molten silicon according to claim 1, wherein a second end of said second portion is welded to a third end of said second rod.
5. The positioning pin for measuring a position of a surface of molten silicon as set forth in claim 1, wherein a cross-sectional shape of the first portion in a direction perpendicular to an axis of the first portion is a quadrangle.
6. The positioning pin for measuring a position of a surface of molten silicon according to claim 5, wherein at least one diagonal line of the quadrangle is parallel to an axis of the second portion.
7. The positioning pin for measuring a position of a surface of molten silicon according to claim 1, wherein a cross-sectional shape of the second portion in a direction perpendicular to an axis of the second portion is a polygon.
8. The positioning pin according to claim 7, wherein the outer peripheral surface of the second portion includes a plurality of side surfaces, each of the side surfaces corresponding to a side of the polygon, wherein the first portion is connected to a first side surface of the plurality of side surfaces, and the first side surface is perpendicular to an axis of the first portion.
9. The locating pin for measuring the position of the surface of a molten silicon as defined in claim 1, wherein the opaque material comprises a graphite material.
10. A crystal silicon melting furnace comprises a guide cylinder, wherein the guide cylinder comprises a top opening and a bottom opening; the positioning pin for measuring the liquid level of the molten silicon is detachably mounted at the bottom of the guide shell according to any one of claims 1 to 9, wherein a mounting hole is formed in the bottom opening of the guide shell, and the first part is inserted into the mounting hole.
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| CN202120221631.1U CN216473570U (en) | 2021-01-26 | 2021-01-26 | Positioning pin for measuring liquid level position of molten silicon and crystal silicon smelting furnace |
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| CN202120221631.1U CN216473570U (en) | 2021-01-26 | 2021-01-26 | Positioning pin for measuring liquid level position of molten silicon and crystal silicon smelting furnace |
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Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN113684532A (en) * | 2020-05-08 | 2021-11-23 | 西安奕斯伟材料科技有限公司 | Molten silicon liquid level ranging assembly for crystalline silicon melting furnace and crystalline silicon melting furnace |
| CN114075694A (en) * | 2020-08-14 | 2022-02-22 | 西安奕斯伟材料科技有限公司 | Detection apparatus for silicon melt liquid level position and single crystal furnace |
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2021
- 2021-01-26 CN CN202120221631.1U patent/CN216473570U/en active Active
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN113684532A (en) * | 2020-05-08 | 2021-11-23 | 西安奕斯伟材料科技有限公司 | Molten silicon liquid level ranging assembly for crystalline silicon melting furnace and crystalline silicon melting furnace |
| CN113684532B (en) * | 2020-05-08 | 2024-08-27 | 西安奕斯伟材料科技股份有限公司 | Silicon melt level ranging assembly for crystal silicon melting furnace and crystal silicon melting furnace |
| CN114075694A (en) * | 2020-08-14 | 2022-02-22 | 西安奕斯伟材料科技有限公司 | Detection apparatus for silicon melt liquid level position and single crystal furnace |
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| TR01 | Transfer of patent right |
Effective date of registration: 20220627 Address after: 710000 room 1-3-029, No. 1888, Xifeng South Road, high tech Zone, Xi'an, Shaanxi Province Patentee after: Xi'an yisiwei Material Technology Co.,Ltd. Patentee after: XI'AN ESWIN SILICON WAFER TECHNOLOGY Co.,Ltd. Address before: Room 1323, block a, city gate, No.1 Jinye Road, high tech Zone, Xi'an, Shaanxi 710065 Patentee before: XI'AN ESWIN SILICON WAFER TECHNOLOGY Co.,Ltd. Patentee before: Xi'an yisiwei Material Technology Co.,Ltd. |
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| CP01 | Change in the name or title of a patent holder |
Address after: 710000 room 1-3-029, No. 1888, Xifeng South Road, high tech Zone, Xi'an, Shaanxi Province Patentee after: Xi'an Yisiwei Material Technology Co.,Ltd. Patentee after: XI'AN ESWIN SILICON WAFER TECHNOLOGY Co.,Ltd. Address before: 710000 room 1-3-029, No. 1888, Xifeng South Road, high tech Zone, Xi'an, Shaanxi Province Patentee before: Xi'an yisiwei Material Technology Co.,Ltd. Patentee before: XI'AN ESWIN SILICON WAFER TECHNOLOGY Co.,Ltd. |