KR20090039248A - Magnetic field magnets for magnetic field-applied Czochralski crystal growth apparatus - Google Patents

Abstract

The present invention relates to a horizontal magnetic field magnet for a magnetic field applied Czochralski crystal growth device (hereinafter referred to as MCZ device), and more particularly, to a large-scale on both sides of a hollow cryostat. A low-temperature space for storing superconducting coils is attached, and a single superconducting coil with a large diameter is placed inside each other to increase the magnetic field, while maintaining a low temperature for the superconducting coil cooling low temperature freezer and current application current. A horizontal magnetic field magnet for an MCZ device integrated in a device.

Description

Horizontal magnetic field magnet for magnetic field-applied Czochralski crystal growth device {Horizontal Magnetic field Magnet For Magnetic field applied Czochralski crystal growth device}

The present invention relates to a horizontal magnetic field magnet for a magnetic field applied Czochralski crystal growth device (hereinafter referred to as MCZ device), and more particularly, to a large-scale on both sides of a hollow low temperature holding device. A low-temperature space for storing superconducting coils is attached, and a single superconducting coil with a large diameter is placed inside each other to increase the magnetic field, while maintaining a low temperature for the superconducting coil cooling low temperature freezer and current application current. A horizontal magnetic field magnet for an MCZ device integrated in a device.

The MCZ device is a device that grows crystals by applying a magnetic field to an existing Czochralski crystal growth device (hereinafter referred to as CZ device).

1 is a conceptual diagram of an MCZ device for explaining the effect of applying a magnetic field to the CZ device.

The CZ apparatus consists of a crucible containing silicon polycrystals, a heater for melting the silicon polycrystals in the crucible, and a lifter for raising the crystals. In the CZ apparatus, the flow of the tropical stream due to the temperature distribution difference in the silicon melt is formed from the wall surface of the quartz crucible to the solid-liquid interface where crystals are formed.

Therefore, vibration occurs at the solid-liquid interface to prevent the formation of single crystals, and impurities eluted from the quartz crucible are incorporated into the crystals, making it difficult to grow high-quality crystals. In order to solve this problem, Czochralski developed the crystal growth method by adjusting the rate of rotating the crucible and the crystal in the opposite direction and controlling the heat by the uniform thermal design of the heater. The wafer was used without problems.

In recent years, however, the MCZ device has been developed to apply a magnetic field to the CZ device because the wafer has been largely enlarged to 300 mm or more and the high quality of the wafer is required due to the low oxygen concentration. It became. Silicon has semiconductor characteristics in the solid state, but when melted and becomes a liquid state, the conductivity increases to have conductor characteristics.

Therefore, as shown in FIG. 1, when a horizontal magnetic field is applied to the solid-liquid interface, the magnetic force acts in the direction of suppressing tropical flow at the crucible wall where the magnetic field direction is perpendicular to the tropical flow, thereby suppressing tropical flow, and from the crucible wall surface. The incorporation of oxygen and impurities is suppressed to enable high quality wafer production.

2 is a conceptual diagram illustrating a horizontal magnetic field magnet installed in the MCZ device of FIG. 1 to provide a horizontal magnetic field.

Referring to Fig. 2, the conventional horizontal magnetic field magnet has a hollow cylindrical cryostat 19 for accommodating the crystal growth path in the central space. The low temperature holding device 19 is vacuum insulated, and two superconducting coils 4a and 4b are disposed to face each other to generate a horizontal magnetic field 7 in the central space.

On the hollow cylindrical low temperature holding device 19, a low temperature freezer 12 and a current applying current lead 11 for cooling the superconducting coils 4a and 4b to maintain a superconducting state are installed.

FIG. 3 is a XY cross-sectional view of the horizontal magnetic field magnet shown in FIG. 2.

Referring to FIG. 3, a double cylindrical liquid helium container 3 is built in a double cylindrical vacuum container 1 to vacuum insulation, and superconducting coils 4a and 4b are mounted opposite to each other in the liquid helium. It is cooled to cryogenic temperature and maintains superconducting state. The cooled superconducting coils 4a and 4b generate the horizontal magnetic field 7 in the central space by applying currents 6a and 6b in the same direction.

Between the vacuum container 1 and the liquid helium container 3, a radiation heat shield 2 is installed to block radiant heat transfer, thereby minimizing heat intrusion by blocking radiant heat transfer from room temperature. In addition, a magnetic shield 10 using pure iron is installed on the outer circumference of the vacuum container 1 to minimize leakage magnetic fields to the outside.

In order to implement the system according to the above-described horizontal magnetic field magnet diagram, the superconducting coils 4a and 4b are installed in the double cylindrical vacuum container 1 in a direction perpendicular to the circumference as shown in FIG. 3. The diameter of 4a, 4b) is limited by the outer diameter of the vacuum container 1.

Even if the diameter of the superconducting coils 4a and 4b is slightly increased in order to increase the intensity of the generated magnetic field, the circumferential length of the vacuum container 1 becomes relatively large and the volume of the device becomes large. In particular, since the circumference of the self-shielding pure iron structure installed on the outer circumference of the cylindrical low temperature maintenance device is significantly increased, there is a problem that the system weight becomes heavy.

As a method of solving such space constraints and generating a strong magnetic field required for large-diameter crystal growth, an integrated multi-coil method shown in FIG. 4 and a separate single coil method shown in FIG. 6 have been developed and put into practical use.

4 is a block diagram of a horizontal magnetic field magnet of an integrated multi-coil method in which the concept of FIG. 2 is applied. The conventional integrated multi-coil horizontal magnetic field magnet has a hollow cylindrical low temperature holding device 19 for accommodating a crystal growth path in a central space, and includes a low temperature freezer 12, a current lead 11, and a superconducting coil ( The points of 4a, 4b, 4c, and 4d that are integrally mounted on one low temperature holding device 19 are the same as those in FIG.

However, instead of increasing the diameter of a single coil as a method of increasing the generated magnetic field strength, two superconducting coils 4a and 4b are disposed adjacent to each other in pairs to exert the effect of a large coil, and a pair of superconducting coils opposite to each other. By installing (4c, 4d), the multi-coil method that generates the horizontal magnetic field 7 in the central space is applied.

That is, the plurality of superconducting coils 4a, 4b, 4c, and 4d are housed in the hollow cylindrical cryogenic holding device 19, and the cryogenic freezer 12 and the current application for current application 11 are placed on the same cryogenic holding device 19. ) Is an integrated multi-coil system in which all components of the magnet are installed in a single cryostat 19.

FIG. 5 is a XY cross-sectional view of the horizontal magnetic field magnet of the integrated multi-coil system shown in FIG. 4. The double cylindrical liquid helium container 3 is embedded in the double cylindrical vacuum container 1 and vacuum-insulated, so that the two pairs of superconducting coils 4a and 4b and the superconducting coils 4c and 4d face each other. It is installed and cooled to cryogenic by liquid helium to maintain the superconducting state. The cooled superconducting coils 4a, 4b, 4c, and 4d generate the horizontal magnetic field 7 in the central space by applying currents 6a, 6b, 6c, and 6d in the same direction.

Between the vacuum container 1 and the liquid helium container 3, a radiation heat shield 2 is installed to block radiant heat transfer, thereby minimizing heat intrusion by blocking radiant heat transfer from room temperature. In addition, a magnetic shield 10 using pure iron is installed on the outer circumference of the vacuum container 1 to minimize leakage magnetic fields to the outside.

FIG. 6 is a block diagram of a horizontal magnetic field magnet of a split single coil type that uses the concept of FIG. 2. The horizontal single-coil magnet of the split type single coil type has the same concept as that of FIG. 2 in that a single superconducting coil 26a and a superconducting coil 26b are disposed to face each other.

However, in order to increase the strength of the generated magnetic field, in order to increase the diameter of the single coil and to secure a free space for accommodating it, a separate type having separate independent cryostats 25a and 25b is used instead of the integrated cryostat. Apply.

That is, large single superconducting coils 26a and 26b are independently embedded in each of the separate cryogenic holding devices 25a and 25b, and the cryogenic freezers 29a and 29b and the current are respectively stored in each of the cryogenic holding devices 25a and 25b. It is a separate single coil type having independent application current leads 28a and 28b.

FIG. 7 is a XY cross-sectional view of a horizontal magnetic field magnet of a split single coil type shown in FIG. 6. Liquid helium containers 24a and 24b are independently embedded in each of the independent vacuum containers 22a and 22b, and superconducting coils 26a and 26b are mounted opposite to each other to apply current in the same direction (6a). 6b) generates a horizontal magnetic field 7 in the central space. Radiation heat shields 23a and 23b are installed between the vacuum vessels 22a and 22b and the liquid helium containers 24a and 24b to block radiant heat transfer, thereby minimizing heat intrusion by blocking radiant heat transfer from room temperature. Magnetic shields 21a and 21b using pure iron are installed on the outer circumference of the vacuum containers 22a and 22b to minimize leakage magnetic fields to the outside.

However, the above-described two types of horizontal magnetic field magnets have disadvantages in the following aspects.

1. As shown in FIG. 5, the horizontal magnetic field magnet of the integrated multi-coil type two superconducting coils 4a and 4b are disposed adjacent to each other in pairs, and the other pair of superconducting coils 4c and 4d are opposed to each other. Installed to generate a horizontal magnetic field (7) in the center space. In this case, between the adjacent superconducting coils (A), strong electromagnetic forces are generated to repel each other, thereby inducing structural deformation of the superconducting coil, which may deteriorate the performance of the magnet.

2. In addition, instead of installing a pair of large superconducting coils facing each other, a horizontal multi-coil magnet has a small superconducting coil of a size that can be accommodated in a vacuum chamber of limited space. That is, currents 6a and 6b in the same direction are applied to a pair of small superconducting coils 4a and 4b disposed adjacent to each other, and in the same direction to another pair of small superconducting coils 4c and 4d opposite to each other. By applying the currents 6c and 6d, the horizontal magnetic field 7 of the desired intensity is generated in the central space. At this time, the direction of the current is reversed in the pair of coil interface adjacent to each other, and thus the direction of the generated magnetic field is reversed to cancel each other, there is a problem that the magnetic field generation efficiency is lowered.

3. As shown in FIG. 6, the horizontal single-coil magnet has a superconducting coil 26a, 26b independently embedded in separate low temperature holding devices 25a, 25b. In addition, the low temperature freezers 29a and 29b and the current application current leads 28a and 28b for cooling the coil to maintain the superconducting state are provided in each of the low temperature holding devices 25a and 25b independently. The largest sources of heat intrusion in superconducting magnet systems are joule heat and heat conduction in the current leads to apply current to the coil. Therefore, in the single-coil type horizontal magnetic field magnet, the superconducting coils 26a and 26b opposite to each other cannot share the same low temperature holding device and the low temperature freezer and current lead attached thereto. Since the separate low temperature freezers 29a and 29b and the separate current leads 28a and 28b must be installed in duplicate, there is a problem in that the cooling cost is increased compared to the integrated type.

4. In addition, as shown in FIG. 7, the horizontal single-coil magnet is provided with superconducting coils 26a and 26b opposed to each other in each of the helium containers 24a and 24, as shown in FIG. The outer periphery of each of the vacuum containers 22a and 22b is provided with magnetic shields 21a and 21b using pure iron to minimize leakage magnetic fields to the outside. Since the magnetic shields 21a and 21b are ferromagnetic materials, very large electromagnetic forces 20a and 20b of tens of tons are pulled between the superconducting coils 26a and 26b.

 However, since the superconducting coils 26a and 26b opposed to each other are mounted on separate helium containers 24a and 24b, the attraction force with the magnetic shields 21a and 21b does not cancel each other and acts as a bias in one direction. Accordingly, the superconducting coil 26a on the right side is attracted in the direction of the magnetic shield 21a on the right side, and the superconducting coil 26b on the left side is attracted by several tens of tons in the direction of the magnetic shield 21a on the left side. In order to support such a large electromagnetic force, a support having a large cross-sectional area is required. However, as the cross-sectional area of the support increases, heat penetration increases. Therefore, the support structure for supporting the electromagnetic force is very complicated, the thickness of the low temperature holding devices (25a, 25b) has a problem because the length of the support to increase in order to reduce heat transfer.

In order to solve the above problems, an object of the present invention is to easily accommodate a large diameter superconducting coil without increasing the overall volume of the system to increase the strength of the generated magnetic field, to the magnetic pole installed in the center of the superconducting coil It is possible to increase the magnetic field generation efficiency, and to provide a horizontal magnetic field magnet for the integrated single-coil MCZ device, in which superconducting coils facing each other share the same low temperature holding device, thereby minimizing the support structure and minimizing the cooling cost. have.

In order to achieve the above object, the horizontal magnetic field magnet for the magnetic field-applied Czochralski crystal growth apparatus according to the present invention opposes each other in the low-temperature space formed on both sides of the hollow-type low temperature holding device and the low temperature holding device and the inside of the low temperature space. Including a pair of superconducting coil and the low temperature freezer for cooling the superconducting coil and the current application for the current, characterized in that the low temperature freezer and the current lead is integrally formed.

And, the low temperature holding device is characterized in that the hollow circular or hollow polyhedron.

In addition, the low temperature space is characterized in that the polyhedron or cylindrical shape.

And, the superconducting coil is characterized in that formed in a circular or ellipse, polygonal shape.

In addition, the cryostat and the low temperature space are formed inside the vacuum vessel and the vacuum vessel inside the radiant train which is formed between the liquid helium container and the vacuum vessel and the liquid helium container in which the superconducting coil is mounted to block radiant heat transfer. And lungs.

Further, the low temperature holding device and a low temperature space outer periphery further comprises a magnetic shield to minimize the leakage magnetic field to the outside.

The magnetic shield may be formed in a shape in which both outer circumferential surfaces or any one outer circumferential surface adjacent to the X-axis direction perpendicular to the magnetic field direction of the superconducting coil are removed.

And, it characterized in that it further comprises a magnetic pole formed in the center of the superconducting coil.

In addition, it is characterized in that the superconducting coil can be directly cooled through the low temperature freezer rather than indirect cooling through the liquid helium.

As described above, the horizontal magnetic field magnet for the MCZ device according to the present invention has the following effects.

In the present invention, since the superconducting coils facing each other are housed in a hexahedral or cylindrical low temperature space attached to both sides of the hollow cryostat, sufficient space is available for the installation of a large diameter superconducting coil without large volume increase of the entire system. Can be provided.

In addition, in the present invention, the cooling cost can be reduced because the large diameter superconducting coils facing each other are housed in the same integrated low temperature holding device, cooled in the same freezer, and current is applied through the same current lead.

In addition, the present invention has a structural advantage that the large diameter superconducting coils opposed to each other are symmetrically attached to the same support to effectively cancel the electromagnetic force between the superconducting coil and the magnetic shield so that it is stably supported without heat intrusion through the additional support. Can be.

In addition, the present invention by attaching the magnetic pole to the center of the large diameter superconducting coils opposed to each other and integrated with the magnetic shield of the outer periphery, while minimizing the loss of the magnetic field while maximizing the magnetic field generation efficiency in the central space where the growth path is located Can provide mold horizontal magnetic field magnet.

Hereinafter, specific embodiments of the present invention will be described in detail with reference to the accompanying drawings.

FIG. 8 is a perspective view schematically illustrating a horizontal magnetic field magnet for an MCZ device according to a first embodiment of the present invention, and FIG. 9 is an XY cross-sectional view of FIG. 8.

8 and 9, the horizontal magnetic field magnet for the MCZ device according to the first embodiment of the present invention is a hollow cylindrical low temperature holding device 32 and a low temperature space 33 of a hexahedron attached to both sides of the low temperature holding device. And a pair of single superconducting coils 31a and 31b, the low temperature freezer 34 for cooling the superconducting coil and the current application current lead 35, which are formed to face each other inside the low temperature space, are integrated into a single low temperature holding device. It may be configured as.

In addition, as shown in FIG. 9, the integrated magnetic coil of the horizontal magnetic field magnet according to the first embodiment has a vacuum container 38 formed inside the low temperature holding device 32 and the low temperature space 33 and vacuum-insulated. The liquid helium container 36 is embedded in the vacuum container 38.

The pair of single superconducting coils 31a and the superconducting coils 31b are installed in the liquid helium container 36 so as to face each other, and are cooled to cryogenic temperature by the liquid helium to maintain a superconducting state.

The cooled superconducting coils 31a and 31b generate the horizontal magnetic field 7 in the central space by applying currents 6a and 6b in the same direction.

In addition, a radiation heat shield 37 is provided between the vacuum vessel 38 and the liquid helium container 36 to block radiant heat transfer, thereby minimizing heat intrusion by blocking radiant heat transfer from room temperature. In addition, a magnetic shield 39 using pure iron is installed on the outer circumference of the vacuum container 38 to minimize leakage magnetic fields to the outside.

The horizontal magnetic field magnet of the integrated single coil type according to the first embodiment is provided with the superconducting coils 31a and 31b in the low-temperature space 33 of the cube, so that the diameter of the superconducting coil is increased to increase the intensity of the generated magnetic field. The superconducting coils 31a and 31b, which are simultaneously opposed, are cooled simultaneously by the same single cryocooler 34 while having the spatial advantage that they can be sufficiently stored without greatly increasing the volume of the hexahedral low-temperature space. Since the current is applied through the pair of current leads 35, the cooling cost is reduced.

In the unitary single coil type horizontal magnetic field magnet according to the first embodiment, as shown in FIG. 9, magnetic shielding 39 using pure iron is installed on the outer circumference of the vacuum container 38 to minimize leakage magnetic fields to the outside.

Since the magnetic shield 39 is a ferromagnetic material, tens of tons of electromagnetic forces 20a and 20b are pulled between the superconducting coils 31a and 31b. However, since the superconducting coils 31a and 31b facing each other are mounted in the same helium container 36, the attraction force with the magnetic shield 39 acts symmetrically and cancels each other. Therefore, stable support is possible without a separate electromagnetic force support.

In the integrated single coil type horizontal magnetic field magnet according to the first embodiment, two superconducting coils 31a and 31b facing each other are magnetically connected to each other by a single magnetic shield 39 as shown in FIG. Therefore, the magnetic flux is not dispersed but is concentrated, so that the magnetic field generating efficiency is increased, and the leakage magnetic field on the X axis is reduced.

FIG. 10 is a perspective view schematically illustrating a horizontal magnetic field magnet for an MCZ device according to a second exemplary embodiment of the present invention, and FIG. 11 is an XY cross-sectional view of FIG. 10.

10 and 11, the second embodiment of the present invention differs only in that the magnetic pole is attached and has the same structure as that of the first embodiment. Therefore, only the differences will be described.

The magnetic field-attached horizontal magnetic field magnet according to the second embodiment attaches a hexahedral low temperature space 33 to both sides of the hollow cylindrical cryostat 32 as shown in FIGS. 10 and 11 and is located inside the low temperature space. Magnetic poles 40a and 40b are provided at the centers of the superconducting coils 31a and 31b to integrate with the magnetic shield 39 on the outer circumference of the vacuum container 38 to maximize the generated magnetic field.

12 is an XY cross-sectional view of a horizontal magnetic field magnet for an MCZ device according to a third exemplary embodiment of the present invention.

Referring to FIG. 12, the third embodiment of the present invention has a configuration in which only the magnetic shield structure is different from the first embodiment of the present invention, and a portion of the magnetic shield on the X axis is emptied.

The portion of the MCZ device where the lifter, which is a steel structure, is installed to maintain magnetic shielding, and the opposite side of the MCZ device can empty the magnetic shield to reduce the weight of the system.

13 is an XY cross-sectional view of a horizontal magnetic field magnet for an MCZ device according to a fourth exemplary embodiment of the present invention.

Referring to FIG. 13, the fourth embodiment of the present invention has a structure in which a magnetic field is increased by further attaching a magnetic pole in the third embodiment.

14 is an XY cross-sectional view of a horizontal magnetic field magnet for an MCZ device according to a fifth exemplary embodiment of the present invention.

Referring to FIG. 14, the fifth embodiment of the present invention is a structure in which the system weight is reduced by emptying the entire magnetic shield on the X axis in the first embodiment.

15 is an XY sectional view of a horizontal magnetic field magnet for an MCZ device according to a sixth embodiment of the present invention.

Referring to FIG. 15, the sixth embodiment of the present invention has a structure in which a magnetic field is increased by attaching a magnetic pole to the fifth embodiment.

16 is a perspective view schematically illustrating a horizontal magnetic field magnet for an MCZ device according to a seventh exemplary embodiment of the present invention.

Referring to FIG. 16, a seventh embodiment of the present invention attaches cylindrical low temperature spaces 33 to both sides of the hollow cylindrical low temperature holding device 32 and faces each other inside the low temperature space 33. Single superconducting coils (31a, 31b) of the unitary, the single-coil horizontal magnetic field of the integrated single coil type to form a super low temperature freezer (34) for cooling the superconducting coil and current application current (35) in one unit It is a magnet.

When a stronger magnetic field is required, magnetic poles 40a and 40b may be installed at the center of the superconducting coils 31a and 31b to maximize the generated magnetic field.

17 is a perspective view schematically illustrating a horizontal magnetic field magnet for an MCZ device according to a seventh embodiment of the present invention.

Referring to FIG. 17, the eighth embodiment of the present invention attaches a hexahedron low temperature space 33 to both sides of the hollow hexahedral low temperature holding device 32, and has a pair of single superconducting coils facing each other therein. 31a, 31b, and a single magnetic coil type horizontal magnetic field magnet, in which the low temperature freezer 34 for cooling superconducting coils and the current application current lead 35 are integrally formed in one low temperature holding device.

When a stronger magnetic field is required, magnetic poles 40a and 40b are installed at the center of the superconducting coils 31a and 31b to maximize the generated magnetic field.

The first, seventh and eighth embodiments relate to the shape of the low temperature holding device 32 and the low temperature space 33, and may be modified in any form as long as the integrated single coil method can be maintained.

18 illustrates a superconducting coil according to a preferred embodiment of the present invention.

Referring to FIG. 18, in the embodiments of the first to eighth embodiments, a horizontal magnetic field may be generated by providing superconducting coils having various shapes of ellipses or polygons instead of circular superconducting coils.

19 is an exemplary view of a direct cooling method according to a preferred embodiment of the present invention.

Referring to FIG. 19, the superconducting state may be maintained by directly cooling a superconducting coil in a low temperature freezer which indirectly cools the superconducting coil with liquid helium in the first to eighth embodiments.

Although the detailed description of the present invention described above has been described with reference to the preferred embodiment of the present invention, the protection scope of the present invention is not limited to the above embodiment, and those skilled in the art will appreciate It will be understood that various modifications and variations can be made in the present invention without departing from the spirit and scope of the invention.

1 is a conceptual diagram of an MCZ device for explaining the effect of applying a magnetic field to the CZ device.

2 is a conceptual diagram illustrating a horizontal magnetic field magnet installed in the MCZ device of FIG. 1 to provide a horizontal magnetic field.

FIG. 3 is a XY cross-sectional view of the horizontal magnetic field magnet shown in FIG. 2.

Figure 4 shows a block diagram of a conventional horizontal magnetic field magnet of the integrated multi-coil system of the concept of FIG.

FIG. 5 is a XY cross-sectional view of the horizontal magnetic field magnet of the integrated multi-coil system shown in FIG. 4.

FIG. 6 is a block diagram of a horizontal magnetic field magnet of a conventional split single coil type in which the concept of FIG. 2 is used.

FIG. 7 is a XY cross-sectional view of a horizontal magnetic field magnet of a split single coil type shown in FIG. 6.

FIG. 8 is a perspective view schematically illustrating a horizontal magnetic field magnet for an MCZ device according to a first embodiment of the present invention, and FIG. 9 is an XY cross-sectional view of FIG. 8.

FIG. 10 is a perspective view schematically illustrating a horizontal magnetic field magnet for an MCZ device according to a second exemplary embodiment of the present invention, and FIG. 11 is an XY cross-sectional view of FIG. 10.

12 is an XY cross-sectional view of a horizontal magnetic field magnet for an MCZ device according to a third exemplary embodiment of the present invention.

13 is an XY cross-sectional view of a horizontal magnetic field magnet for an MCZ device according to a fourth exemplary embodiment of the present invention.

14 is an XY cross-sectional view of a horizontal magnetic field magnet for an MCZ device according to a fifth exemplary embodiment of the present invention.

15 is an XY sectional view of a horizontal magnetic field magnet for an MCZ device according to a sixth embodiment of the present invention.

16 is a perspective view schematically illustrating a horizontal magnetic field magnet for an MCZ device according to a seventh exemplary embodiment of the present invention.

17 is a perspective view schematically illustrating a horizontal magnetic field magnet for an MCZ device according to a seventh embodiment of the present invention.

18 illustrates a superconducting coil according to a preferred embodiment of the present invention.

19 is an exemplary view of a direct cooling method according to a preferred embodiment of the present invention.

* Description of the symbols for the main parts of the drawings *

32: low temperature holding device 33: low temperature space

31a, 31b: superconducting coil 34: freezer

35 current lead 36 liquid helium container

37: radiant heat shield 38: vacuum vessel

39: magnetic shield 40a, 40b: stimulation

Claims (9)

A hollow cryostat; A low temperature space formed on both sides of the low temperature holding device; A pair of superconducting coils facing each other in the low temperature space; A low temperature freezer for cooling the superconducting coil; Including current lead for current application, Magnetic field-applied Czochralski crystal growth apparatus horizontal magnetic field magnet, characterized in that the low-temperature freezer and the current lead is integrally formed. The method of claim 1, The low temperature holding device A horizontal magnetic field magnet for magnetic field applying Czochralski crystal growth apparatus, characterized in that the hollow cylindrical or hollow polyhedron. The method of claim 1, The low temperature space A horizontal magnetic field magnet for a magnetic field application type Czochralski crystalline field device, characterized in that it is polyhedral or cylindrical. The method of claim 1, The superconducting coil A horizontal magnetic field magnet for a magnetic field-applied Czochralski crystal growth apparatus, characterized in that formed in the formation of any one selected from a circle, an ellipse and a polygonal shape. The method of claim 1, The low temperature holding device and the low temperature space A vacuum vessel inside; A liquid helium container formed inside the vacuum container and mounted with the superconducting coil; And a magnetic field applied to the magnetic field-applied Czochralski crystal growth apparatus, characterized in that it comprises a radiation heat shield formed between the vacuum vessel and the liquid helium vessel to block radiant heat transfer. The method of claim 1, On the outer space of the low temperature holding device and the low temperature space Magnetic field-applied Czochralski crystal growth apparatus, the horizontal magnetic field magnet further comprises a magnetic shield to minimize the leakage magnetic field to the outside. The method of claim 6, The magnetic shield is A horizontal magnetic field magnet for a magnetic field-applied Czochralski crystal growth apparatus, characterized in that the outer circumferential surface adjacent to the X-axis direction perpendicular to the magnetic field direction of the superconducting coil is formed in a shape in which one outer circumferential surface is removed. The method according to any one of claims 1 to 7, Magnetic field-applied Czochralski crystal growth apparatus horizontal magnetic field magnet further comprises a magnetic pole formed in the center of the superconducting coil. The method of claim 1, The low temperature freezer A horizontal magnetic field magnet for magnetic field-applied Czochralski crystal growth apparatus, characterized in that the superconducting coil is directly cooled.

Images