KR101903032B1 - Zone refining apparatus for producting high purity tin - Google Patents

Abstract

A zone melting refining apparatus for high purity tin production is disclosed. The zone melting refining apparatus for high purity tin production according to the present invention includes a boat for containing tin metal, power supply means for outputting a high frequency current, at least one induction coil for forming a melting zone at a heated position by being supplied with the high frequency current from the power supply means and locally heating the tin metal, at least one cooling block for cooling the melting zone in accordance with the direction of movement of the boat and moving impurities contained in the tin metal in the same direction as the movement direction of the boat, and control means for performing a refining step including a melting step, a stabilization step, and a transport step and performing control such that the movement or non-movement of the boat and the intensity of the high frequency current output from the power supply means vary in accordance with the refining step.

Description

TECHNICAL FIELD [0001] The present invention relates to a zeolite refining apparatus for producing high purity tin,

The present invention relates to a band melting apparatus for producing high purity tin, and more particularly, to a band melting apparatus for producing high purity tin capable of producing 6N-grade high purity tin by purifying the impurity- ≪ / RTI >

With the development of mobile technology, high performance and intelligence of industrial and consumer electronic products such as IOT, wearable, and electronic medical equipment are required, and the performance of electronic components is rapidly improving. In order to cope with the high performance of such mobile products, the reliability, low power, miniaturization, and the like of components are inevitably required. Particularly, in order to cope with low power and miniaturization as a mobile part, a SiP (System in Package) for integrating a plurality of chips into one package or a PiP (Package in Package) technology for connecting several chip packages in one package Is being developed.

Among them, a flip chip is a technology for directly connecting a chip and a substrate through a solder. In the flip chip, tin (Sn) has been widely used together with lead (Pb) as a solder material connecting chip and substrate or substrate and PCB substrate. However, lead free solder replacing Pb / Has been greatly increased. To date, tin alloys or pure tin solders containing 3% silver (Ag) or 1.5% silver and copper (Cu) have been used as substitutes for lead, and thus the importance of tin Is expected to increase gradually.

Conventional metal refining techniques including tin may be selected from a variety of methods depending on the type of metal to be refined, the content of impurities, the required purity, and the like. In particular, high purity technologies include electrolytic refining, vacuum melting, Purification, and zone refinig. Of these, the band refining technology is widely used in the semiconductor field because it has a relatively high stability because it moves a relatively small melting zone and is easily applicable to a substance showing a difference in solubility between impurities in a high-volume solution.

Despite these advantages, band refining techniques have been regarded as less efficient for metals with melting points below 600 ° C. That is, it is conventional practice that tin has a melting point of about 250 DEG C and is not suitable for refining by a general band refining technique. Further, since the band refining technique depends on the concentration distribution depending on the difference of melting points of the components between the two interfaces, There is a limit in which a certain degree of impurity distribution necessarily occurs. Therefore, there is a need to develop a technique that can efficiently remove impurities contained in tin metal, while improving the productivity of refined flakes.

Korean Patent No. 10-0958652 Korean Patent No. 10-1580495

One aspect of the present invention provides a band melting and refining apparatus for producing high purity tin capable of purifying 6N-grade high purity tin while taking economic efficiency and productivity into consideration when refining tin.

The technical problem of the present invention is not limited to the technical problems mentioned above, and other technical problems which are not mentioned can be understood by those skilled in the art from the following description.

A band melting apparatus for producing a high purity tin according to an embodiment of the present invention includes a boat for receiving a tin metal, a power supply means for outputting a high frequency current, a power supply means for applying a high frequency current from the power supply means, At least one induction coil for heating the molten zone to form a melting zone at a heated position, cooling the molten zone according to the direction in which the boat moves, A stabilizing step, and a conveying step, wherein at least one of the cooling block, the stabilizing step, and the conveying step is carried out in accordance with the purifying step, And a control means for controlling the control means so as to be variable.

Wherein the control unit controls the intensity of the high frequency current applied to the melting step to be greater than the intensity of the high frequency current applied to the stabilizing step and controls the intensity of the high frequency current applied to the stabilizing step It can be controlled to be larger than the intensity of the high-frequency current.

Wherein the control means controls the boat to be stopped when it is determined that the purification step is any one of the melting step and the stabilization step and if the purification step is determined to be the transfer step, So that it can be controlled.

Wherein the controlling means changes the intensity of the high-frequency current in each of the refining steps so that the melting zone has a predetermined shape while performing the refining step, wherein the predetermined shape is a shape in which the boundary is concave with respect to the center of the melting zone Shape.

The induction coil is disposed so as to pass through the central portion while the boat moves, and the cooling block is provided with a heat dissipator.

The induction coil and the cooling block may be provided in plural numbers, and the induction coil and the cooling block may be alternately arranged.

When a plurality of induction coils are provided, each of the induction coils is equipped with a ferrite core for controlling the flow of a high frequency current to be applied to each induction coil so that the induction coils are heated at the same heating temperature and heating time .

The ferrite core may block a high-frequency current flowing in an upper direction of the induction coil, and may pass a high-frequency current flowing to a side surface and a lower portion of the induction coil.

And a vacuum chamber for receiving the heating means and the boat and for maintaining the inside of the vacuum chamber so that the purification step is performed in a vacuum state.

And a gas supply unit for injecting an insoluble gas into the vacuum chamber so as to perform a pretreatment process for removing an oxide film formed on the surface of the tin metal.

According to one aspect of the present invention, the moving speed of the boat and the heating temperature by the high-frequency heat source can be varied according to the purification step, so that high-purity tin can be manufactured. By the ferrite core mounted on each of the plurality of induction coils, So that the productivity and efficiency of the tin tablet can be improved.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a schematic diagram showing components of a band melting apparatus for producing high purity tin according to an embodiment of the present invention; FIG.
2 is a perspective view showing an example of the apparatus of FIG.
Figs. 3 to 6 are views showing the specific configuration and function of the purification means of Fig. 1. Fig.
Figs. 7 to 10 are views showing an example of specific functions of the control means of Fig. 1. Fig.

The following detailed description of the invention refers to the accompanying drawings, which illustrate, by way of illustration, specific embodiments in which the invention may be practiced. These embodiments are described in sufficient detail to enable those skilled in the art to practice the invention. It should be understood that the various embodiments of the present invention are different, but need not be mutually exclusive. For example, certain features, structures, and characteristics described herein may be implemented in other embodiments without departing from the spirit and scope of the invention in connection with an embodiment. It is also to be understood that the position or arrangement of the individual components within each disclosed embodiment may be varied without departing from the spirit and scope of the invention. The following detailed description is, therefore, not to be taken in a limiting sense, and the scope of the present invention is to be limited only by the appended claims, along with the full scope of equivalents to which such claims are entitled, if properly explained. In the drawings, like reference numerals refer to the same or similar functions throughout the several views.

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

1 is a perspective view showing a schematic configuration of a band melting apparatus 1 for manufacturing high purity tin according to an embodiment of the present invention.

Specifically, a band melting apparatus 1 for producing high purity tin according to an embodiment of the present invention includes a boat 10, a power supply means 20, a refining means 30, a cooling means 40, (50).

The boat 10 may be a vessel for receiving tin metal, which is the metal to be refined. The boat 10 is shaped like a letter "D" having an open upper surface, and may be formed in a direction parallel to the ground. Further, the boat 10 can be moved in a predetermined direction by the control means 40 described later. Such a boat 10 may be made of quartz or alumina. However, the shape and material of the boat 10 are not limited to the above-described examples, and may be variously modified depending on the purification environment.

The power supply means 20 may be a device for applying a high-frequency current. The power supply means 20 does not limit the type or size of the power source so long as it is a power source capable of applying an alternating current between 0 kHz and 30 kHz.

The refining means 30 can locally heat the tin metal by receiving the high frequency current generated by the power supply means 20. [ That is, the refining means 30 can form a melting zone in any one portion of the tin metal and maintain the temperature and width of the melting zone constant. The refining means 30 cools the melting zone in accordance with the direction in which the boat 10 moves, so that the impurities contained in the tin metal can be moved in the same direction as the moving direction of the boat 10.

To this end, the purifying means 30 can be composed of at least one induction coil 31 and at least one cooling block 32, and the specific configuration and function of the purifying means 30 including them can be found in FIG. 2 And will be described later.

The cooling means 40 may be a device for keeping the temperature of the purifying means 30 constant. The cooling means 40 may include a first cooler (not shown) for controlling the temperature of the induction coil 31 and a second cooler (not shown) for controlling the temperature of the cooling block 32. The cooling means 40 can be controlled so that the respective constituents are maintained at a predetermined constant temperature in the process of manufacturing the high purity tin from the tin metal. For example, the first cooler may control the temperature of the induction coil 31 to be maintained at 23 ° C to 25 ° C, and the second cooler may control the temperature of the cooling block 32 to be maintained at 3 ° C to 5 ° C have. However, the temperatures of the induction coil 31 and the cooling block 32 are not limited to those described above, and may vary depending on the season, weather, usage environment, etc. In some cases, . In this case, the cooling means 40 may be constituted by one cooler, and one cooler may control the temperature of the induction coil 31 and the cooling block 32 independently.

The control means 50 may be an apparatus for controlling the overall operation of the band melting apparatus 1 for producing high purity tin according to the present invention.

That is, the control means 50 controls the moving and moving speed of the boat 10, controls the on / off or the applied current amount of the high frequency output section 20, Temperature can be controlled.

More specifically, the control means 50 can control the high-frequency current to flow through the induction coil 31 to control the melting zone to be formed by melting any one portion of the tin metal contained in the boat. Then, the control means 50 can control the existing melting zone to be crystallized by moving the boat 10 in a certain direction. As the tin metal is cooled, the impurities (segregation) contained in the tin metal migrate along the direction opposite to the moving direction of the boat 10, and when the tin metal is melted and crystallized as a whole, So that the impurities can flocculate.

In addition, the control means 50 divides the band melting process into a melting step, a stabilizing step, and a moving step, and varies the amount of high frequency current applied from the high frequency output section 20 so as to apply different amounts of current to each step, Can be controlled. The specific function of the control means 50 will be described later with reference to Fig.

The band melting apparatus 1 for producing high purity tin according to the present invention may further comprise a vacuum chamber 60 and a gas supply means 70.

The vacuum chamber 60 may be a kind of housing that provides a space in vacuum to perform the band melting purification process in a vacuum environment. The booth 10 and the heating means 20 are disposed in the vacuum chamber 60 and the same environmental condition can be formed in the melting and crystallization process of the tin metal by the vacuum chamber 60. The vacuum chamber 60 is connected to a vacuum pump (not shown), and the vacuum pump may be a device controlled to keep the inside of the vacuum chamber 60 in a vacuum state.

The gas supply means 70 may be a device for performing a pretreatment process of tin metal. The gas supply means 70 can supply nitrogen (N 2) gas, which is an insoluble gas, into the vacuum chamber 60 so as to remove the oxide film formed on the surface of the tin metal. Hereinafter, detailed configurations and functions of the main components of FIG. 1 will be described in detail.

Fig. 2 to Fig. 4 are diagrams showing specific configurations of the purifying means 30 of Fig.

2, the purifying means 30 according to an embodiment of the present invention may be an apparatus including at least one induction coil 31 and at least one cooling block 32. [

The induction coil 31 is a device for locally heating the tin metal by receiving a high frequency current generated by the power supply means 20. [ The induction coil 31 can cause induction heating phenomenon by a high frequency current which is an alternating current. That is, an induction electromotive force is generated in the induction coil 31 as a high frequency current flows, and an eddy current is generated in the induction coil 31 by the induction electromotive force. Thus, the eddy current causes the boat 10 disposed inside the induction coil 31 to be heated, and as a result, the tin metal inside the boat 10 can be indirectly heated and melted.

Further, in one embodiment of the present invention, a plurality of such induction coils 31 may be provided. When a plurality of induction coils 31 are provided, the high frequency currents applied by one power supply means 20 are applied in series or in parallel, and the amount of current applied to each induction coil 31 may be different. For example, when a plurality of induction coils 31 are connected in parallel to each other, the amount of current applied to each induction coil 31 must be the same in an ideal environment. However, in a commercial manufacturing environment, The amount of current to be substantially applied by the resistance component having a minute difference for each coil 31 may be different.

To this end, a ferrite core 33 may be mounted on each induction coil 31. The ferrite core 33 is a module for controlling the high frequency current applied to the induction coil 31 to be applied at a constant intensity.

3 to 4, a specific shape of the induction coil 31 according to an embodiment of the present invention is shown.

As shown in the figure, the ferrite core 33 may be mounted on a certain portion of the induction coil 31. At this time, the direction of the high frequency current applied by the ferrite core 33 can be controlled in the induction coil 31. For example, the ferrite core 33 may be mounted so as to protrude from the outer side surface of the induction coil 31. In other words, the payload core 33 can be mounted such that a high-frequency current is prevented from flowing to the upper portion of the induction coil 31, and current flows only to the side and the bottom. In this case, since no current is applied to the upper portion of the induction coil 31, the tin metal is not heated near the upper portion, and eddy current may be generated only on the side surface and the lower surface. As a result, the induction coil 31 has the effect of indirectly heating only the portion where the boat 10 is formed by the ferrite core 33.

Further, as described above, the ferrite core 33 allows the plurality of induction coils 31 to receive the same current intensity, so that the same melting and crystallization level can be maintained between the induction coils.

Referring again to FIG. 2, the cooling block 32 may be provided with a space such as a cylinder or a square column. The internal temperature of the cooling block 32 may be maintained at a predetermined temperature by the cooling unit 40 described above.

The cooling block 32 may cool the melting zone formed by locally heating the tin metal to change the existing melting zone to the crystallization zone. Specifically, as the melting zone is cooled by the cooling block 32, the impurities present in the melting zone can migrate toward the boundary of the melting zone side due to the tendency to make crystals of the same materials when the tin is recrystallized. A concrete description related to this will be described later.

5 to 6, a band melting apparatus 1 for producing high purity tin according to an embodiment of the present invention includes a plurality of induction coils 31 and cooling blocks 32 And the induction coil 31 and the cooling block 32 can be arranged alternately. For example, when the band melting apparatus 1 for producing high purity tin is composed of two induction coils 31 and two cooling blocks 32, the first induction coil 31_1 to the first cooling block 32_1 The second induction coil 31_2, and the second cooling block 32_2. At this time, it is preferable to determine the order and position of the induction coil and the cooling block in consideration of the moving direction of the boat 10 so that the band refining process proceeds with pre-melting and post-cooling.

The first induction coil 31_1 and the second induction coil 31_2 may be spaced apart from each other by a predetermined interval. Here, the preset interval means that as the boat 10 moves, the melting zone formed by the first induction coil 31_1 is converted into the cooling band while passing through the first cooling block 32_1, and at the same time, And may be a distance between the first induction coil 31_1 and the second induction coil 31_2 that is set to be able to convert into the melting zone.

5 (a), in the first purification process using the band melting apparatus 1 for producing high purity tin according to the present invention, the boat 10 includes a first induction coil 31_1 and a second induction coil 31_1. The second induction coil 31_2 can be disposed at a position where the tin metal can be melted at the same time.

For example, when the moving direction of the boat 10 is the right direction, and each induction coil of the band melting apparatus 1 for producing high-purity tin according to the present invention forms a melting zone having a width of 10 cm, The position of the first boat 10 can be arranged so that the right boundary of the boat 10 is located at least 5 cm from the center of the second induction coil 31_2 to the right. That is, the initial position of the boat 10 can be arranged such that a plurality of induction coils arranged in accordance with the moving direction of the boat 10 can simultaneously melt the tin metal. At the same time, the initial position of the boat 10 can be shifted from the induction coils disposed at the outermost of the plurality of induction coils in the moving direction by a predetermined interval set based on the melt band. Accordingly, at the time of initial refining of the tin metal, a melting zone can be formed simultaneously in a plurality of induction coils.

5 (b), the initially formed melting zone can be moved in the same direction as the moving direction of the boat 10 as the boat 10 moves. That is, the melting zone formed by the first induction coil 31_1 moves toward the first cooling block 32_1 and the melting zone (molten tin metal) moving into the first cooling block 32_1 is gradually crystallized Cooling band.

As shown in Fig. 5 (c), if the melting zone formed by the first induction coil 31_1 passes completely through the first cooling block 32_1, the entire melting zone can be changed to the cooling zone . At this time, at the time when the melting zone formed by the first induction coil 31_1 completely passes through the first cooling block 32_1, the second induction coil 32_1 is located at a position where the first melting zone converted into the cooling zone can be melted again. (31_2) may be disposed.

That is, the second induction coil 31_2 may be spaced apart from the first induction coil 31_1 by a predetermined interval. Here, the preset interval is set such that, at the time when the melting zone formed by the first induction coil 31_1 completely passes through the first cooling block 32_1, the first melting zone converted into the cooling zone is melted again The first induction coil 31_1 and the second induction coil 31_2 may be spaced apart from each other.

By analyzing the structure and performance of the band melting apparatus 1 for producing a high purity tin according to the present invention, the width of the cooling block and the width of the melting zone formed by the induction coil Can be extracted. The first induction coil 31_1 and the first cooling block 32_1 are arranged at the positions set by the manager so that the positions of the first induction coil 31_1 and the first cooling block 32_1 are coordinate- Can be extracted. Then, the position of the second induction coil 31_2 can be determined by reflecting the coordinate information of the first cooling block 32_1, the width of the first cooling block 32_1, and the width of the melting zone. The arrangement interval between the two induction coils can be calculated based on the coordinate information of the first induction coil 31_1 and the second induction coil 31_2 whose positions are determined. Finally, the calculated batch interval can be determined at a preset interval. Thereafter, the spacing between the plurality of induction coils can be spaced apart by a predetermined predetermined interval. However, the method of setting the predetermined interval is not limited to the example described above. As described above, at the time when the melting zone formed by the first induction coil 31_1 completely passes through the first cooling block 32_1, As long as the second induction coil 31_2 is disposed at a position where the first molten band converted into the band can be melted again, the predetermined interval can be calculated by various methods.

On the other hand, another example of determining the positions of the plurality of induction coils and the plurality of cooling blocks is shown in Fig.

As shown, according to another embodiment of the present invention, not only each induction coil but also a cooling block can be arranged at a predetermined position. That is, the first cooling block 32_1 may be disposed at a predetermined distance from the first induction coil 31_1.

Specifically, the width of the first cooling block 32_1 can be designed to be equal to the width of the melting zone formed by the induction coil, and the melting zone formed by the first induction coil 31_1 can be moved At a point where it can be cooled immediately. In addition, the second induction coil 31_2 can be disposed at a position where the melting zone formed by the first induction coil 31_1 can be immediately melted at the time when it completely passes through the first cooling block 32_1.

To this end, when the moving direction of the boat 10 is the right direction, the first cooling block 32_1 is configured such that the left side surface of the first cooling block 32_1 is in contact with the melting zone of the first induction coil 31_1 At a position spaced apart by a half of the width of the protrusion. The second induction coil 32_1 may be disposed such that the center axis is located at a position spaced apart from the right side surface of the first cooling block 32_1 by 1/2 of the width of the melting zone. In other words, the first cooling block 32_1 may be disposed so that the central portion thereof is located at a position spaced apart from the central portion of the first induction coil 31_1 by the width of the melting zone, and the second induction coil 32_1 And the center portion may be located at a position spaced apart from the center portion of the block 32_1 by the width of the melting zone. As a result, the first cooling block 31_1 and the second cooling block 31_2 can be disposed apart from each other by twice the width of the melting zone. According to the above-described method of disposing the induction coil and the cooling block according to another embodiment of the present invention, the melting zone formed by the first induction coil 31_1 can be instantaneously changed to the cooling zone in the transport step described later, It can be completely melted at the time when the entire melting zone is converted into the cooling zone by completely passing through the block.

7 to 8 are graphs showing flows controlled in the band melting process by the control means 50 in Fig.

As described above, the control means 50 can separate and control the band melting apparatus 1 for producing high purity tin according to the present invention in each purification step.

Here, the purification step may include a melting step 110, a stabilization step 120 and a transfer step 130.

The melting step 110 may be a step of locally heating the tin metal and heating it until the heated part is melted. That is, in the melting step 110, the control means 50 can control to apply a relatively high high-frequency current to the induction coil 31 to accelerate the time at which the tin metal reaches the melting point.

The stabilizing step 120 may be a step of forming a melting zone generated in the melting step 110 into a predetermined shape and keeping it constant. In the stabilization step 120, the width of the melting zone is enlarged by a predetermined width. Accordingly, in the melting step 110, the temperature of the tin metal is controlled to be continuously increased, while in the stabilizing step 120, the tin metal is slowly heated to adjust the width of the melting zone, . ≪ / RTI >

Specifically, when the stabilization step 120 is performed, the control means 50 can control the shape of the melting zone to have a predetermined shape. Here, the predetermined shape is characterized in that the boundary line of the melting zone is concave with respect to the center of the melting zone. Further, the control means 50 can control so that the overall shape of the concave shaped melting zone determined in the stabilization step 120 is not deformed. A detailed description related to this will be given later.

The transferring step 130 may be a process of transferring the molten zone formed in the stabilizing step 120 to the cooling block while maintaining the molten zone. The control means 50 can control to apply a relatively low current to the induction coil 31 so that the molten band is kept constant in the transfer step 130. [

On the other hand, if the induction coil 31 and the cooling block 32 are provided in plural, the purification step 100 is performed in the first induction coil and the cooling block, and the purification step is repeated in the second induction coil and the cooling block .

Referring to Fig. 7, an example in which the control means 50 performs the above purification step is shown.

The control means 50 may perform the respective purification steps for a predetermined time interval. Also, the control means 50 can control the movement and the moving speed of the boat 10 and the intensity of the high frequency current applied to the induction coil 31 to vary according to the step in the current process.

First, when an operation signal is inputted from a user, the control unit 50 controls the band melting apparatus 10 for producing high purity tin until a preset time interval (for example, 170 seconds) (110). In the melting step 100, the control means 50 can control the output of the power supply means 20 such that 10-15 A / 2.3 Kw is applied to the induction coil 31. Then, the control means 50 can control so that the boat 50 is stopped without being moved.

Then, the control means 50 may control the stabilization step 120 to be performed for any one of the time periods from 50 to 150 seconds from the end of the melting step 110. At this time, the control means 50 can control the intensity of the current applied to the induction coil 31 to be 5 ~ 10A. That is, the control means 50 may set the intensity of the current applied to the stabilization step 120 to a value smaller than the intensity of the current applied in the melting step 110. [

Finally, the control means 50 can control the band melting apparatus 1 for high purity tin production to perform the transferring step 130 after the stabilization step 120 has been operated for a predetermined time period. In the transfer step 130, the control means 50 can control the boat 10 to move at a speed of 0.5 mm / min to 2.0 mm / min. In addition, the control means 50 can control the induction coil 31 to apply a current (5-8A) smaller in magnitude than the current intensity applied to the stabilization step 120. [

At this time, the band melting apparatus 1 for producing high purity tin according to the present invention can control the moving direction of the impurities by the control means 50 performing the above-described purification step. Specifically, the control unit 50 may control the melting zone formed on the tin metal to be formed in a concave shape at the boundary with respect to the center in the refining step 100.

8 to 9 together show an example of the direction in which the impurities move according to the shape of the melting zone.

8 (a) shows an example of a melting zone formed by the band melting apparatus 1 for producing high purity tin according to the present invention. When the moving direction of the boat 10 is from left to right, the illustrated cooling zone can be the initial melting zone. That is, the control means 50 indirectly heats the tin metal during the melting step 110 to control the formation of the melting zone, equalizes the temperature of the melting zone during the stabilization step 120, So that the boundary between the band and the tin metal can be controlled to be constant. Then, when the transferring step 130 is started, the control means 50 can move the boat 10 to the right to cool the initially formed melting zone by the cooling block 32. [

In this process, the melting zone is changed to the cooling (recrystallization) zone, and the melting zone shown in the tin metal in the left portion of the initial melting zone can be formed. In the process of gradually cooling the first molten zone from the right side to the left side opposite to the moving direction of the boat 10, the impurities contained in the tin metal are still cooled due to the tendency of the same material (tin) To the melting zone, which is not yet established. That is, the impurities move near the left boundary line of the melting zone, and can be moved and rearranged in a direction opposite to the moving direction of the boat 10 as a whole.

At this time, when the melting zone is a convex shape as shown in Figs. 8 (b) and 9 (a), the impurities can be dispersed toward both wall surfaces of the boat during the cooling process. When the melting zone is a flat shape as shown in FIG. 8 (c), the impurities may be evenly dispersed during the cooling process and the purification efficiency may be lowered. On the other hand, when the melting zone is a concave shape as shown in Figs. 8 (a) and 9 (b), the refining efficiency can be increased since the impurities move toward the center during the cooling process. On the other hand, if the melting zone is controlled to have a concave shape, the width of the melting zone described above with reference to FIGS. 5 to 6 can be determined on the basis of the outermost protruding portion.

According to the experimental results, when the high-frequency current applied to the induction coil 31 is applied at an appropriate level, that is, within a preset critical section, the melting zone can be formed in a concave shape with respect to the center. Further, as the intensity of the applied high frequency current becomes larger, the melting zone can be deformed from a concave shape to a flat shape, or from a flat shape to a convex shape.

10, the filling rate of the tin metal filled in the boat 10 is filled up by a predetermined ratio (for example, 40%), and the ratio of the tin metal filled in the boat 10 Under the condition that the center portion coincides with the melting point, the melting zone can be formed and maintained in a concave shape when performed according to the purification step disclosed in Fig. 5 described above. However, these conditions are not limited to the above-described examples, and may be adjusted to various values depending on the use environment. For example, when the filling rate of the tin metal accommodated in the boat 10 is set to 50% to increase the production amount of the tin to be refined, the intensity of the high frequency current applied to each of the refining steps may be larger than the above- The moving speed of the moving body 10 can be reduced.

As described above, the control means 50 controls the intensity of the high-frequency current applied to the induction coil 31, the temperature of the cooling block 32, and the movement speed and movement speed of the boat 10 according to the above- It is possible to control the melting zone to be formed while being formed into a concave shape. As a result, in the case of purifying the tin metal by using the band melting apparatus (1) for producing high purity tin according to the present invention, it is possible to control the flow direction of the impurities so as to be concentrated at one point of the impurities, Can be increased.

While the present invention has been particularly shown and described with reference to exemplary embodiments thereof, it will be understood by those skilled in the art that various changes and modifications may be made therein without departing from the spirit and scope of the invention as defined in the appended claims. It will be possible.

10: Boat
20: Power supply means
30: Heating means
40: cooling means
50: control means
60: vacuum chamber
70: gas supply means

Claims (11)

Boats for receiving tin metal;
Power supply means for outputting a high-frequency current;
At least one induction coil receiving a high frequency current from the power supply means and locally heating the tin metal to form a melting zone at a heated position;
At least one cooling block for cooling the molten zone according to a direction in which the boat moves and moving the impurities contained in the tin metal in a predetermined direction; And
A stabilizing step and a conveying step are carried out to control the movement of the boat according to the purifying step or to control the movement of the boat according to the purifying step so that the intensity of the high- And control means for controlling the molten zone to be maintained in a predetermined shape,
Wherein the induction coil and the cooling block are arranged such that,
And a cooling zone for cooling the tin metal that has passed through the melting zone and the melting zone at a designated position along a direction in which the boat moves, Lt; / RTI &
The predetermined shape to be held in the melting zone is,
A boundary line is curved with respect to the center of the melting zone,
Wherein the melting zone and the cooling zone are formed by a melt-
Wherein a width at which each band is formed is determined according to at least one of a structure and a performance of the induction coil and the cooling block,
The predetermined interval may be,
The induction coil is set to be equal to the width of the band formed according to at least one of the characteristics of the structure and the performance of the induction coil and the cooling block so that the induction coil is located at the center of the melting zone and spaced apart by half the width of the band Wherein the cooling block is located and the melting zone and the cooling zone are continuously formed,
The boat,
Wherein the width of the cooling zone is longer than the sum of the widths of the melting zone and the cooling zone.
The method according to claim 1,
Wherein,
Controlling the intensity of the high-frequency current applied to the melting step to be greater than the intensity of the high-frequency current applied to the stabilizing step,
Wherein the control unit controls the intensity of the high-frequency current applied to the stabilization step to be greater than the intensity of the high-frequency current applied to the conveying step.
The method according to claim 1,
Wherein,
And controlling the boat to be stopped when it is determined that the refining step is one of the melting step and the stabilizing step,
And controlling the boat to move at a predetermined speed when the purification step is determined as the transferring step. The method according to claim 1,
Wherein,
Controlling the moving speed and the moving speed of the boat according to the purifying step, changing the strength of the high-frequency current according to the purifying step so that the melting zone is formed in a predetermined shape while performing the purifying step, , The stabilizing step and the transferring step are performed for different predetermined times,
The predetermined shape is a shape,
Characterized in that the boundary is concave with respect to the center of the melting zone.
The method according to claim 1,
The induction coil is arranged to pass through the center portion while the boat moves,
Wherein the cooling block is provided with a heat dissipator therein.
The method according to claim 1,
Wherein the induction coil and the cooling block are provided in plural,
Characterized in that the induction coil and the cooling block are alternately arranged.
The method according to claim 6,
The induction coil and the cooling block are alternately arranged,
The first induction coil, the first cooling block, the second induction coil, and the second cooling block are sequentially disposed on the basis of the moving direction of the boat,
Wherein the second induction coil
Wherein the molten zone formed by the first induction coil is converted into a cooling zone while passing through the first cooling block as the boat moves and is disposed at a position for converting the cooling zone into a melting zone again, A band melting purification apparatus for manufacturing.
The method according to claim 6,
When a plurality of induction coils are provided,
Characterized in that a ferrite core for controlling the flow of high frequency current applied to each induction coil is mounted so that the plurality of induction coils are heated at the same heating temperature and heating time.
9. The method of claim 8,
Wherein the ferrite core comprises:
A high frequency current flowing in an upper direction of the induction coil is cut off,
And a high-frequency current flowing to the side surface and the lower portion of the induction coil is passed through the band-pass filter.
The method according to claim 1,
Further comprising a vacuum chamber for receiving the induction coil, the cooling block and the boat, the vacuum chamber maintaining the interior in a vacuum so that the purification step is performed in a vacuum state.
11. The method of claim 10,
Further comprising gas supply means for injecting an insoluble gas into the vacuum chamber so as to perform a pretreatment process for removing an oxide film formed on the surface of the tin metal.

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