阅读说明：本技术 一种应用于单晶炉的冷却装置及单晶炉 (cooling device applied to single crystal furnace and single crystal furnace ) 是由 邓先亮 于 2018-07-20 设计创作，主要内容包括：本发明提供一种应用于单晶炉的冷却装置及单晶炉,用于拉制高质量单晶硅棒,其特征在于,所述冷却装置包括：水冷套,所述水冷套包括设置在所述水冷套中的环形冷却水循环管路；导热附件,固定连接在所述水冷套的底端并向下延伸部分长度,用于吸收单晶硅棒的热量并传导至所述水冷套进行冷却,其中,所述导热附件的中心设置有空腔,以允许所述单晶硅棒通过,合理控制液面上部温度分布调节单晶硅棒的冷却速率以控制单晶硅棒内部缺陷。(The invention provides cooling devices applied to a single crystal furnace and the single crystal furnace, which are used for drawing high-quality single crystal silicon rods and are characterized in that the cooling devices comprise a water cooling jacket, a heat conduction accessory and a heat conduction accessory, wherein the water cooling jacket comprises an annular cooling water circulation pipeline arranged in the water cooling jacket, the heat conduction accessory is fixedly connected to the bottom end of the water cooling jacket and extends downwards for a part of length, the heat conduction accessory is used for absorbing the heat of the single crystal silicon rods and conducting the heat to the water cooling jacket for cooling, a cavity is arranged in the center of the heat conduction accessory to allow the single crystal silicon rods to pass through, and the temperature distribution on the upper part of a liquid level is reasonably controlled to adjust the cooling rate of.)

1, A cooling device for a single crystal furnace, used for drawing a high quality single crystal silicon rod, wherein the cooling device comprises:

the water cooling jacket comprises an annular cooling water circulation pipeline arranged in the water cooling jacket;

and the heat conduction accessory is fixedly connected to the bottom end of the water cooling sleeve and extends downwards for a part of length, and is used for absorbing the heat of the silicon single crystal rod and conducting the heat to the water cooling sleeve for cooling, wherein a cavity is formed in the center of the heat conduction accessory to allow the silicon single crystal rod to pass through, and the temperature distribution on the upper part of the liquid level is reasonably controlled to adjust the cooling rate of the silicon single crystal rod so as to control the internal defects of the silicon single crystal rod.

2. The cooling apparatus of claim 1, wherein said thermally conductive attachment comprises at least thermally conductive cartridges attached to a bottom end of said water jacket.

3. The cooling apparatus of claim 1, wherein the thermally conductive attachment includes at least two thermally conductive cartridges having different thermal conductivities.

4. The cooling device as claimed in claim 2, wherein a plurality of heat conduction cylinders with different inner diameters are sleeved from outside to inside and connected at , or the inner cavities of a plurality of heat conduction cylinders are opposite and stacked from top to bottom and connected at .

5. The cooling device of claim 1, wherein the heat conducting attachment comprises a th heat conducting cylinder and a second heat conducting cylinder sleeved at , wherein the bottom end of the th heat conducting cylinder portion further extends to cover the bottom surface of the second heat conducting cylinder.

6. The cooling apparatus as claimed in claim 5, wherein part of the th heat transfer cylinder is fixedly connected to the outer side wall of the water cooling jacket, and the top end surface of the second heat transfer cylinder is connected to the bottom end surface of the water cooling jacket.

7. The cooling apparatus of claim 1, wherein the heat transfer attachment comprises an th heat transfer barrel and a second heat transfer barrel, wherein a top end face of the th heat transfer barrel is connected to a bottom end face of the water cooling jacket, and a top end face of the second heat transfer barrel is connected to a bottom end face of the th heat transfer barrel.

8. The cooling device as claimed in claim 7, wherein the water cooling jacket comprises a pipe body, the top end surface of the th heat-conducting cylinder is connected with the bottom end surface of the pipe body, and the thickness of the wall of the th heat-conducting cylinder is gradually reduced from bottom to top to be less than or equal to the thickness of the wall of the pipe body.

9. The cooling apparatus as claimed in claim 7, wherein the thickness of the wall of the second heat-conducting cylinder is equal to the thickness of the wall of the bottom end of the heat-conducting cylinder.

10. The cooling apparatus as claimed in claim 5 or 7, wherein the thermal conductivity of the th heat-conducting cylinder is greater than the thermal conductivity of the second heat-conducting cylinder, or the thermal conductivity of the second heat-conducting cylinder is greater than the thermal conductivity of the th heat-conducting cylinder.

11. The cooling apparatus as claimed in claim 1, wherein the top end inner diameter of the heat conducting attachment is the same as the bottom end outer diameter of the water cooling jacket.

12. The cooling apparatus of claim 2, wherein the heat conducting cylinder is cylindrical, conical, truncated conical, or a combination thereof.

13. The cooling apparatus of claim 1, wherein the material of the thermally conductive attachment comprises at least of thermal insulation, graphite, quartz, tungsten, and molybdenum.

14. The cooling apparatus of claim 1, wherein the thermally conductive appendage has an inner diameter in the range of 360mm to 600 mm.

15. The cooling device of claim 2, wherein the wall thickness of the thermally conductive cartridge ranges from 10mm to 250 mm.

16. The cooling apparatus of claim 1, wherein the water jacket further comprises:

the annular cooling water circulation pipeline is arranged in the pipe wall of the pipe body, and cooling water circulates in the annular cooling water circulation pipeline;

the flange is arranged at the top end of the pipe body and used for installing the water cooling jacket in the single crystal furnace;

and the heat absorption layer covers the surface of the outer side wall of the tube body.

17. The cooling apparatus as claimed in claim 16, wherein the material of the pipe body comprises stainless steel, and the annular cooling water circulation line comprises a copper pipe.

18, A single crystal furnace for drawing a defect-free single crystal silicon rod, the single crystal furnace comprising:

a furnace body with a furnace chamber inside;

the crucible is arranged in the furnace cavity;

the cooling apparatus of of claims 1-17, disposed within the furnace chamber above the crucible, wherein a bottom end surface of the thermally conductive appendage is above a maximum level of molten liquid in the crucible within the single crystal furnace.

19. The single crystal furnace of claim 18, further comprising:

the furnace cover is positioned at the upper part of the furnace body;

and the auxiliary chamber is positioned above the furnace cover, and the top end of the water cooling sleeve is fixedly arranged between the furnace cover and the auxiliary chamber.

20. The single crystal furnace as claimed in claim 18, wherein a flange is provided at a top end of the water cooling jacket, and the flange is fixedly provided between the furnace cover and the sub-chamber.

21. The single crystal furnace of claim 18, further comprising:

the heat-insulating layer is arranged on the inner wall of the furnace body,

the top end of the guide cylinder is fixedly connected to the top end face of the heat preservation layer, the bottom end of the guide cylinder is located above the crucible, and a gap is reserved between the heat conduction accessory and the guide cylinder.

Technical Field

The invention relates to the field of crystal growth equipment, in particular to cooling devices applied to a single crystal furnace and the single crystal furnace.

Background

The artificial crystal plays an increasingly important role in the fields of science and technology and industrial production, particularly, monocrystalline silicon is used as semiconductor materials and is applied to integrated circuits and other electronic components more and more .

Meanwhile, in the semiconductor industry, with the development of high-end processes, the design rule of Integrated Circuits (ICs) is decreasing, and the feature line width is gradually developing below 10 nm. Higher requirements are placed on defect control in semiconductor silicon wafer fabrication, requiring crystal defects to be controlled at smaller scales to meet the higher requirements. In order to meet the quality requirement of the high-specification silicon wafer, the V/G (V single crystal pulling speed and G axial temperature gradient) ratio of a solid-liquid interface can not meet the requirement only by controlling, and the thermal history of the crystal needs to be strictly controlled.

Therefore, from the viewpoint of both economical efficiency and crystal quality control, it is necessary to propose new cooling apparatuses and single crystal furnaces to solve the above-mentioned technical problems.

Disclosure of Invention

The concept of series in simplified form is introduced in the summary of the invention section, which is described in further detail in the detailed description section the summary of the invention is not intended to identify key features or essential features of the claimed subject matter, nor is it intended to be used to identify key features or essential features of the claimed subject matter.

In view of the defects of the prior art, the aspect of the invention provides cooling devices applied to a single crystal furnace, which are used for drawing a high-quality silicon single crystal rod, wherein the cooling devices comprise:

the water cooling jacket comprises an annular cooling water circulation pipeline arranged in the water cooling jacket;

and the heat conduction accessory is fixedly connected to the bottom end of the water cooling sleeve and extends downwards for a part of length, and is used for absorbing the heat of the silicon single crystal rod and conducting the heat to the water cooling sleeve for cooling, wherein a cavity is formed in the center of the heat conduction accessory to allow the silicon single crystal rod to pass through, and the temperature distribution on the upper part of the liquid level is reasonably controlled to adjust the cooling rate of the silicon single crystal rod so as to control the internal defects of the silicon single crystal rod.

Illustratively, the thermally conductive attachment includes at least thermally conductive cartridges attached to a bottom end of the water jacket.

Illustratively, the thermally conductive attachment includes at least two thermally conductive cartridges having different thermal conductivities.

Illustratively, a plurality of heat conducting cylinders with different inner diameters are sleeved from outside to inside and connected at , or the inner cavities of the heat conducting cylinders are opposite and stacked from top to bottom and connected at .

Illustratively, the heat conducting accessory comprises a heat conducting cylinder and a second heat conducting cylinder which are sleeved at , wherein the bottom end of the part of the heat conducting cylinder also extends to cover the bottom surface of the second heat conducting cylinder.

Illustratively, part of the th heat conduction cylinder is fixedly connected with the outer side wall of the water cooling jacket, and the top end surface of the second heat conduction cylinder is connected with the bottom end surface of the water cooling jacket.

Illustratively, the heat conducting attachment comprises an th heat conducting cylinder and a second heat conducting cylinder, wherein the top end surface of the th heat conducting cylinder is connected with the bottom end surface of the water cooling jacket, and the top end surface of the second heat conducting cylinder is connected with the bottom end surface of the th heat conducting cylinder.

Illustratively, the water cooling jacket comprises a pipe body, wherein the top end surface of the heat conduction cylinder is connected with the bottom end surface of the pipe body, and the thickness of the cylinder wall of the heat conduction cylinder is gradually reduced from bottom to top to be less than or equal to the thickness of the pipe wall of the pipe body.

Illustratively, the thickness of the wall of the second heat-conducting cylinder is equal to the thickness of the wall of the bottom end of the heat-conducting cylinder.

Illustratively, the thermal conductivity of the th thermal conductive barrel is greater than the thermal conductivity of the second thermal conductive barrel, or the thermal conductivity of the second thermal conductive barrel is greater than the thermal conductivity of the th thermal conductive barrel.

Illustratively, the inner diameter of the top end of the heat conducting accessory is the same as the outer diameter of the bottom end of the water cooling jacket.

Illustratively, the shape of the heat conducting cylinder is cylindrical, conical, truncated cone, or a combination thereof.

Illustratively, the material of the thermally conductive attachment includes at least of thermal insulation, graphite, quartz, tungsten, and molybdenum.

Illustratively, the thermally conductive attachment has an inner diameter in the range of 360mm to 600 mm.

Illustratively, the wall thickness of the heat-conducting cylinder ranges from 10mm to 250 mm.

Exemplarily, the water cooling jacket further comprises:

the annular cooling water circulation pipeline is arranged in the pipe wall of the pipe body, and cooling water circulates in the annular cooling water circulation pipeline;

the flange is arranged at the top end of the pipe body and used for installing the water cooling jacket in the single crystal furnace;

and the heat absorption layer covers the surface of the outer side wall of the tube body.

Illustratively, the material of the pipe body comprises stainless steel, and the annular cooling water circulation pipeline comprises a copper pipe.

In another aspect, the invention provides single crystal furnaces for pulling defect free single crystal silicon rods, the single crystal furnaces comprising:

a furnace body with a furnace chamber inside;

the crucible is arranged in the furnace cavity;

the cooling device is arranged in a furnace cavity above the crucible, wherein the bottom end surface of the heat conducting accessory is positioned above the highest liquid level of the molten liquid in the crucible in the single crystal furnace.

Illustratively, the single crystal furnace further comprises:

the furnace cover is positioned at the upper part of the furnace body;

and the auxiliary chamber is positioned above the furnace cover, and the top end of the water cooling sleeve is fixedly arranged between the furnace cover and the auxiliary chamber.

Illustratively, a flange is arranged at the top end of the water cooling jacket and is fixedly arranged between the furnace cover and the auxiliary chamber.

Illustratively, the single crystal furnace further comprises:

the heat-insulating layer is arranged on the inner wall of the furnace body,

the top end of the guide cylinder is fixedly connected to the top end face of the heat preservation layer, the bottom end of the guide cylinder is located above the crucible, and a gap is reserved between the heat conduction accessory and the guide cylinder.

The cooling device comprises a water cooling sleeve and a heat conduction accessory connected to the bottom end of the water cooling sleeve, the heat of the silicon single crystal rod is absorbed and conducted to the water cooling sleeve for cooling by utilizing the heat conductivity of the heat conduction accessory, wherein a cavity is formed in the center of the heat conduction accessory to allow the silicon single crystal rod to pass through, the temperature distribution of the upper part of a liquid level is reasonably controlled to adjust the cooling rate of the silicon single crystal rod so as to control the internal defects of the silicon single crystal rod, and the heat conduction accessory absorbs the heat of the silicon single crystal rod and conducts the heat to the water cooling sleeve for cooling, so that the grown silicon single crystal rod is cooled in time to provide power for the growth of a single crystal, the pulling speed is.

Drawings

The following drawings of the present invention are included to provide an understanding of the invention as part of and are included to provide a further understanding of the invention.

In the drawings:

FIG. 1 shows a schematic partial cross-sectional view of an embodiment single crystal furnace of the present invention;

FIG. 2A shows a schematic cross-sectional view of an embodiment of a cooling device of the present invention;

fig. 2B shows a schematic cross-sectional view of another embodiments of the cooling device of the present invention.

Detailed Description

In the following description, numerous specific details are set forth in order to provide a thorough understanding of the present invention, however, it will be apparent to those skilled in the art that the present invention may be practiced without or more of these details.

It is to be understood that the present invention may be embodied in many different forms and should not be construed as limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the invention to those skilled in the art. In the drawings, the size and relative sizes of layers and regions may be exaggerated for clarity. Like reference numerals refer to like elements throughout.

It will be understood that when an element or layer is referred to as being "on.. another," "adjacent to.," connected to, "or" coupled to "other elements or layers, it can be directly on, adjacent to, connected to, or coupled to the other elements or layers, or intervening elements or layers may be present.

For example, if the device in the figures is turned over, then elements or features described as "below" or "beneath" would then be oriented "on" other elements or features.

As used herein, the singular forms "," "," and "the/the" are intended to include the plural forms as well, unless the context clearly indicates otherwise, it is also to be understood that the terms "comprises" and/or "comprising," when used in this specification, specify the presence of stated features, integers, steps, operations, elements, and/or components, but do not preclude the presence or addition of or more other features, integers, steps, operations, elements, components, and/or groups thereof.

In order to provide a thorough understanding of the present invention, a detailed structure will be set forth in the following description in order to explain the present invention. The following detailed description of the preferred embodiments of the invention, however, the invention is capable of other embodiments in addition to those detailed.

At present, in order to improve the pulling speed of the monocrystalline silicon prepared by the Czochralski method, a water cooling jacket is introduced, the time for preparing crystal bars is greatly shortened, the cost is saved, meanwhile, in the semiconductor industry, along with the continuous development of high-end processing procedures, the IC design rule is continuously reduced, the characteristic line width gradually develops below 10nm, higher requirements on defect control are provided for the semiconductor silicon wafer manufacturing, when the defect size of a substrate material is more than 1/3 of the ULSI characteristic line width, the substrate material becomes a fatal defect, the device can be failed, and therefore, the crystal defect needs to be controlled in a smaller scale to meet the higher requirements.

In order to meet the quality requirement of the high-specification silicon wafer, the V/G (V single crystal pulling speed and G axial temperature gradient of the solid-liquid interface) ratio of the solid-liquid interface cannot be met only by controlling the V/G ratio, and the thermal history of the crystal needs to be strictly controlled.

In order to overcome the defects of the conventional water cooling sleeve in the aspect of accurate control of crystal cooling heat history and control the internal defects of the single crystal silicon rod, cooling devices applied to a single crystal furnace are provided in the application and used for drawing a high-quality single crystal silicon rod, and the cooling devices mainly comprise:

the water cooling jacket comprises an annular cooling water circulation pipeline arranged in the water cooling jacket;

and the heat conduction accessory is fixedly connected to the bottom end of the water cooling sleeve and extends downwards for a part of length, and is used for absorbing the heat of the silicon single crystal rod and conducting the heat to the water cooling sleeve for cooling, wherein a cavity is formed in the center of the heat conduction accessory to allow the silicon single crystal rod to pass through, and the temperature distribution on the upper part of the liquid level is reasonably controlled to adjust the cooling rate of the silicon single crystal rod so as to control the internal defects of the silicon single crystal rod.

The cooling device comprises a water cooling sleeve and a heat conduction accessory connected to the bottom end of the water cooling sleeve, the heat of the silicon single crystal rod is absorbed and conducted to the water cooling sleeve for cooling by utilizing the heat conductivity of the heat conduction accessory, wherein a cavity is formed in the center of the heat conduction accessory to allow the silicon single crystal rod to pass through, the temperature distribution of the upper part of a liquid level is reasonably controlled to adjust the cooling rate of the silicon single crystal rod so as to control the internal defects of the silicon single crystal rod, and the heat conduction accessory absorbs the heat of the silicon single crystal rod and conducts the heat to the water cooling sleeve for cooling, so that the grown silicon single crystal rod is cooled in time to provide power for the growth of a single crystal.

The cooling apparatus for a single crystal furnace and the single crystal furnace including the same according to the present invention will be described in detail with reference to fig. 1, 2A and 2B, in which fig. 1 shows a partial sectional view of embodiments of the single crystal furnace according to the present invention, fig. 2A shows a sectional view of embodiments of the cooling apparatus according to the present invention, and fig. 2B shows a sectional view of another embodiments of the cooling apparatus according to the present invention.

As an example, as shown in fig. 1, the single crystal furnace 1 includes a furnace body in which a furnace chamber 11 is provided, a furnace cover 17, and a sub-chamber (not shown), wherein the furnace cover 17 is located at an upper portion of the furnace body, the sub-chamber is located above the furnace cover 17, and a grown single crystal silicon rod is cooled to a room temperature in the sub-chamber.

In examples, a crucible is disposed in the furnace chamber 11 for holding molten silicon material, wherein the crucible comprises a graphite crucible 13 and a quartz crucible 12 disposed from bottom to top, that is, the quartz crucible 12 is disposed in the graphite crucible 13, and when in use, the quartz crucible 12 holds molten silicon material.

Illustratively, an insulating layer 18 is arranged on the inner wall of the furnace body and used for isolating heat exchange with the outside and stabilizing a thermal field in the furnace cavity. The material of the insulating layer 18 may be any insulating material suitable for a single crystal furnace, which can both perform an insulating function and withstand high temperature in the single crystal furnace, for example, the material of the insulating layer 18 may be a carbonized or graphitized carbon fiber felt.

, the crucible further comprises a crucible tray 14 and a crucible support shaft 15, wherein the crucible tray 14 is disposed below the crucible, for example, below the graphite crucible 13, and is connected to the crucible support shaft 15, wherein the crucible support shaft 15 is further disposed on the inner wall of the bottom of the furnace body through the insulating layer 18 at the bottom of the furnace body, and the crucible support shaft 15 is used for supporting the crucible tray 14 and driving the crucible to lift and rotate.

In examples, the single crystal furnace further comprises a side heater 16 disposed outside the crucible, the side heater 16 is cylindrically surrounded outside the crucible for heating the silicon raw material in the crucible to form a silicon solution and forming a thermal field, for example, outside the graphite crucible 13, alternatively, the side heater 16 may be any suitable side heater 16 known to those skilled in the art, such as a graphite heater, which is made of graphite or carbon fiber and has conductivity, alternatively, an electrode quartz sheath (not shown) made of quartz material is sleeved around the side heater 16 for electrical insulation.

In examples, the silicon single crystal silicon rod growth device further comprises a guide flow cylinder 19, wherein the guide flow cylinder 19 is arranged above the crucible, the bottom end of the guide flow cylinder is arranged in the crucible, as shown in fig. 1, the bottom end of the guide flow cylinder 19 is arranged in the quartz crucible 12, the top end of the guide flow cylinder 19 is connected with the top end of the heat preservation layer 18, the guide flow cylinder 19 surrounds the single crystal silicon rod growth area, the guide flow cylinder is used for isolating heat generated by the heater and guiding air flow circulation, the direct heat radiation of high-temperature molten silicon materials in the heater and the furnace body to the single crystal silicon rod is blocked, the temperature of the single crystal silicon rod is reduced, and meanwhile, the guide flow cylinder enables argon blown downwards from.

the single crystal furnace further includes a cooling device disposed in a furnace chamber above the crucible, such as a furnace chamber above the quartz crucible 12, for pulling a high quality single crystal silicon rod, as shown in FIG. 1.

Wherein, as shown in fig. 1, the cooling device comprises a water cooling jacket 20 and a heat conducting attachment 21 fixedly connected to the bottom end of the water cooling jacket 20 and extending a part of the length downwards, wherein the water cooling jacket 20 and the heat conducting attachment 21 are only shown in the form of blank boxes for the sake of simplicity, and the specific structure thereof is described in detail in the following.

In the examples, the water-cooled jacket 20 was placed at its top end between the lid of the furnace and the sub-chamber, as shown in fig. 1, and the water-cooled jacket 20 extended through the lid of the furnace into the furnace chamber above the crucible.

, the bottom end surface of the heat conducting attachment 21 is located above the highest liquid level of the molten liquid (such as molten silicon material) in the crucible in the single crystal furnace, and the bottom end surface of the heat conducting attachment can be as close to the highest liquid level as possible without affecting the crystal growth, so that the high temperature part of the single crystal silicon rod just grown can be cooled in time.

In cases, the heat conducting attachment 21 is located in the guide shell and spaced from the guide shell 19. in , as shown in fig. 1, the heat conducting attachment 21 is centrally provided with a cavity to allow the single crystal silicon rod to pass through, the cavity having a size larger than the diameter of the single crystal silicon rod.

For explanation and explanation of the detailed structure of the cooling device, the cooling device in two embodiments is described below with reference to fig. 2A and 2B.

In examples, as shown in fig. 2A and 2B, the cooling device comprises a water jacket 20, wherein the water jacket 20 comprises a flange 201, a pipe body 202 and an annular cooling water circulation line 203 arranged in the water jacket 20. illustratively, the annular cooling water circulation line 203 is arranged in the pipe wall of the pipe body 202, wherein cooling water circulates in the annular cooling water circulation line, the annular cooling water circulation line 203 is composed of a plurality of pipes arranged in the water jacket at intervals up and down, and the annular cooling water circulation line 203 can be a copper pipe or other suitable materials.

Illustratively, as shown in fig. 2A and 2B, a flange 201 is provided at the top end of the tube 202 for mounting the water cooling jacket 20 in the single crystal furnace, for example, the flange 201 is fixedly provided between the furnace cover 17 and the sub-chamber, and is fixed on the furnace body between the furnace cover 17 and the sub-chamber, so that the whole water cooling jacket is mounted in the furnace cavity of the single crystal furnace.

In cases, in order to make the water jacket absorb heat better, the inner and outer side wall surfaces of the tube 202 are covered with heat absorbing layers (not shown), which may be any suitable material, especially black material with good heat absorption.

The cooling water which is introduced into the annular cooling water circulation pipeline 203 and can be at room temperature or the cooling water which is cooled to be lower than the room temperature is subjected to heat exchange with the high-temperature silicon single crystal rod to be rapidly cooled.

In examples, the material of the flange 201 and the tube 202 included in the water jacket 20 may be any material having good thermal conductivity and high temperature resistance, such as a metal material, wherein the flange 201 and the tube 202 are preferably stainless steel.

Illustratively, the cooling device further includes various devices for supplying cooling water to the annular cooling water circulation pipeline 203, such as a water chiller, a water tank, and a water inlet pipe and a water outlet pipe, so that the cooling water is always circulated in the annular cooling water circulation pipeline, and the devices may use any suitable devices known to those skilled in the art, and are not limited thereto.

, the cooling device comprises a heat conducting accessory 21 fixedly connected with the bottom end of the water cooling jacket and extending downwards for a part of the length, wherein the heat conducting accessory comprises at least heat conducting cylinders connected with the bottom end of the water cooling jacket, the number and the shape of the heat conducting cylinders can be reasonably selected and changed according to the actual temperature distribution, and the shape of the heat conducting cylinders is cylindrical (namely cylindrical), conical, truncated cone-shaped or the combination of the cylindrical, conical and truncated cone-shaped, and the purpose of accurately controlling the temperature gradient distribution of the crystal is achieved through the change of the shape.

In examples, the inside diameter of the top end of the heat conducting accessory 21 is the same as the outside diameter of the bottom end of the water cooling jacket 20.

In cases, the heat conducting accessory comprises at least two heat conducting cylinders with different heat conductivities, the heat conducting cylinders with different heat conductivities can be prepared by using materials with different heat conductivities, the heat conductivity of the whole heat conducting accessory is adjusted by reasonably selecting the materials with proper heat conductivities, and the temperature distribution of the upper part of the liquid level is reasonably controlled to accurately control the temperature of the crystal, wherein the liquid level refers to the liquid level of the molten silicon material in the crucible.

In another cases, the heat conduction cylinders with different inner diameters of the heat conduction accessory are sleeved from outside to inside and connected to , the top end of each heat conduction cylinder is connected to the bottom end of the water cooling jacket, or alternatively, steps can be further performed, the bottom end of the outermost heat conduction cylinder extends inwards to cover the bottom surfaces of all the heat conduction cylinders located at the inner side, and part of the inner side wall of the outermost heat conduction cylinder is connected to the outer side wall of the water cooling jacket, so that the stability of the connection between the heat conduction accessory and the water cooling jacket can be increased, wherein the cavity allowing the single crystal silicon rod to pass through in the heat conduction accessory 21 is formed by the cavity in the heat conduction cylinder, and the size of the innermost heat conduction cylinder is larger than the diameter of the single crystal silicon rod, so as to ensure that the single crystal silicon rod can pass through the heat.

In embodiments, as shown in fig. 2A, the heat conducting attachment 21 includes a th heat conducting cylinder 211 and a second heat conducting cylinder 212 sleeved on , wherein a part of the bottom end of the th heat conducting cylinder 211 further extends to cover the bottom surface of the second heat conducting cylinder 212, wherein a part of the inner wall of the th heat conducting cylinder 211 is fixedly connected to the outer side wall of the water cooling jacket 20, i.e., to the outer side wall of the tube body 202, the top end surface of the second heat conducting cylinder 212 is connected to the bottom end surface of the water cooling jacket 20, i.e., to the bottom end surface of the tube body 202, or alternatively, a part of the outer side wall of the th heat conducting cylinder 211 is connected to the inner side wall of the water cooling jacket, the top end surface of the second heat conducting cylinder 212 is connected to the bottom end surface of the water cooling jacket 20, and a part of the bottom end of the th heat conducting cylinder 211 further extends to.

In examples, the th heat conduction cylinder is connected with the adjacent side wall of the second heat conduction cylinder, or as shown in fig. 2A, a space is formed between the adjacent side walls of the th heat conduction cylinder 211 and the second heat conduction cylinder 212.

In this embodiment, as shown in fig. 2A, the material of the th heat-conducting cylinder 211 is graphite, and the material of the second heat-conducting cylinder 212 is quartz, wherein the thermal conductivity of the th heat-conducting cylinder 211 is greater than that of the second heat-conducting cylinder 212, or the thermal conductivity of the second heat-conducting cylinder 212 is greater than that of the th heat-conducting cylinder 211.

In another examples, the heat conducting cartridges have their internal cavities stacked and connected to in an opposite manner from top to bottom, for example, as shown in fig. 2B, the heat conducting attachment comprises a th heat conducting cartridge 211 and a second heat conducting cartridge 212, wherein the top end surface of the th heat conducting cartridge 211 is connected to the bottom end surface of the water cooling jacket 20, and the top end surface of the second heat conducting cartridge 212 is connected to the bottom end surface of the th heat conducting cartridge 211.

The plurality of heat-conducting cylinders may be connected two by two using any suitable means, such as welding or screwing. When the plurality of heat conduction cylinders have different heat conductivities, the cooling speed of the silicon single crystal rod in each heat conduction cylinder is different, and the temperature distribution of the upper part of the liquid level can be controlled by selecting the proper combination of the heat conduction cylinders and utilizing the difference of the heat conductivity.

In cases, the water cooling jacket 20 includes a pipe body 202, the top end surface of the heat conduction cylinder 211 is connected to the bottom end surface of the pipe body 202, wherein the thickness of the cylinder wall of the th heat conduction cylinder 211 is gradually reduced from bottom to top to be less than or equal to the thickness of the pipe wall of the pipe body 202, so that the cross-sectional shape of the cylinder wall of the th heat conduction cylinder 211 is trapezoidal, and the thickness of the cylinder wall of the second heat conduction cylinder 212 is equal to the thickness of the cylinder wall of the th heat conduction cylinder 211 at the bottom end.

In the structure of the heat conductive attachment 21 shown in fig. 2B, the th heat conductive cylinder is in a truncated cone shape, and the second heat conductive cylinder is in a cylindrical shape, and heat conductive cylinders of two different shapes are connected to , or the th heat conductive cylinder may be in a truncated cone shape, and the second heat conductive cylinder may be in a cylindrical shape, or both the th heat conductive cylinder and the second heat conductive cylinder may be in a truncated cone shape.

In addition, in the structure shown in fig. 2B, the thermal conductivity of the th heat conduction cylinder 211 is greater than that of the second heat conduction cylinder 212, or the thermal conductivity of the second heat conduction cylinder 212 is greater than that of the th heat conduction cylinder 211, in this embodiment, the material of the th heat conduction cylinder 211 is graphite, the material of the second heat conduction cylinder 212 is quartz, and the thermal conductivities of graphite and quartz are different, wherein the thermal conductivity of graphite is greater than that of quartz.

Moreover, by changing the shape of the heat-conducting cylinder, the heat-conducting accessory shown in fig. 2A has better heat conductivity than the heat-conducting accessory shown in fig. 2B, and the cooling of the heat-conducting accessory is faster, and the heat-conducting accessories with different heat transfer properties can be formed by selecting appropriate shape change according to different thermal fields, so that the control of the temperature distribution on the upper part of the liquid surface is achieved.

In this embodiment, the heat conduction tube may be connected to the water cooling jacket by any suitable means, including but not limited to welding, or by screwing.

Optionally, the material of the heat conducting accessory (such as the heat conducting cylinder) comprises at least of heat insulating material, graphite, quartz, tungsten and molybdenum, or other materials with heat conductivity and high temperature resistance, wherein the heat insulating material can comprise carbonized or graphitized carbon fiber felt.

The inner diameter of the heat conducting attachment 21 is kept or slightly different from the inner diameter of the water cooling jacket, for example, the inner diameter of the heat conducting attachment ranges from 360mm to 600mm, that is, the inner diameter of the innermost heat conducting cylinder ranges from 360mm to 600 mm.

Alternatively, the thickness of the wall of the heat-conducting cylinder ranges from 10mm to 250mm, for example, in the structure shown in fig. 2A, the sum of the thicknesses of the walls of the th heat-conducting cylinder 211 and the second heat-conducting cylinder 212 ranges from 10mm to 250mm, while in the structure shown in fig. 2B, the thickness of the wall of each of the th heat-conducting cylinder 211 and the second heat-conducting cylinder 212 may range from 10mm to 250mm, which is only an example, and other suitable thicknesses may also be suitable for the present invention.

The cooling device and the single crystal furnace including the cooling device of the present invention have been described so far, and the complete cooling device and the single crystal furnace may include other elements, which are not described in detail in .

Because the silicon single crystal rod is formed by solidifying the molten silicon material, the temperature gradient of the solid-liquid interface of the silicon single crystal rod plays an important role in the quality of the formed silicon single crystal rod in the solidification process, for example, the temperature gradient of the solid-liquid interface in a solid body is too large, so that the silicon single crystal rod is easy to formInterstitial silicon atoms and even dislocation groups are generated in the formed ingot, and vacancies and even COP defects are easily formed in the solid-liquid interface when the temperature gradient in the solid is too small, and the proper V/G affects the quality of the ingot, the concentration of single crystal point defects is related to V/G, when the V/G is equal to or more than a certain critical value, the concentration of interstitial atoms is reduced, when the V/G is less than a certain critical value, the concentration of vacancies is very small, and the two critical values are about 1.3 x 10^-3cm^-2min^-1K^-1(or 2.2X 10)^-5cm^-2sec^-1K^-1) Left and right. Therefore, it is more difficult to cause a proper V/G at the temperature difference between the inside and outside of the large-diameter ingot. In the technical scheme of the invention, as the heat conduction accessory is arranged below the water cooling jacket, the heat conduction accessories with different heat transfer properties are formed by carrying out different shape designs and heat conduction material selections, so that the accurate control of the temperature at the upper part of the liquid level is achieved, the temperature gradient of a solid-liquid interface is adjusted, the internal and external difference and the oxygen precipitation degree of the crystal bar of the crystal temperature gradient are further accurately controlled, the density of COP defects and dislocation groups during production is reduced, and the silicon single crystal bar without defects (such as COP defects and dislocation groups) is produced, and the quality and the production efficiency of the produced silicon single crystal bar are finally improved.

Defects are inevitably grown in the process of preparing the silicon single crystal, and the processes of recombination, nucleation and growth after the defects are generated need to be accurately controlled to prepare the high-quality crystal. The generation of the defects and the subsequent related physical and chemical changes have direct relation with the temperature, so that the accurate control of the temperature distribution of the crystal has important significance for controlling the generation and the growth of the defects. And because the temperature can be accurately controlled in the scheme of the invention, the compounding, nucleation and growing processes after the generation of the defects can be avoided, the size and the number of the internal defects of the single crystal silicon rod are controlled, the high-quality single crystal silicon rod is straightened finally, the requirement of the silicon wafer with lower characteristic line width is met, taking COP defects as an example, the single crystal silicon rod can rapidly pass through a temperature region (such as 900 ℃ -1100 ℃) with the fastest COP defect growth speed due to the addition of a water cooling sleeve and a heat conduction accessory to the cooling effect, so that the growth of the COP defects is effectively prevented, and the internal defects of the single crystal silicon rod are controlled.

In addition, the cooling water in the water cooling jacket can exchange heat with the monocrystalline silicon rod to cool the monocrystalline silicon, so that the heat of the monocrystalline silicon rod is quickly dissipated, the growth rate of the monocrystalline silicon rod can be increased, the production rate is increased, and the production cost is saved.

The present invention has been illustrated by the above embodiments, but it should be understood that the above embodiments are for illustrative and descriptive purposes only and are not intended to limit the invention to the scope of the described embodiments. Furthermore, it will be understood by those skilled in the art that the present invention is not limited to the embodiments described above, and that many variations and modifications may be made in accordance with the teachings of the present invention, which variations and modifications are within the scope of the present invention as claimed. The scope of the invention is defined by the appended claims and equivalents thereof.