KR20120070080A - Single crystal growth device - Google Patents

Abstract

PURPOSE: An apparatus for growing a single crystal sapphire ingot is provided to grow an ingot at a stable temperature gradient by including a cooling member in a crucible and a chamber. CONSTITUTION: A cooling member(105) comprises an inner chamber(112) and an outer chamber(113). The inner chamber is installed near a crucible. The outer chamber is integrated with the outside of the inner chamber. Cooling water reversely circulates in the inner chamber and the outer chamber to reduce temperature difference between the upper side and the lower side of the crucible.

Description

Single Crystal Sapphire Ingot Growth Device {SINGLE CRYSTAL GROWTH DEVICE}

The present invention relates to a single crystal sapphire ingot growth apparatus, and more particularly, to provide a growth apparatus capable of improving the quality of the sapphire ingot manufactured by improving the cooling means and the weighing means of the growth apparatus for the Kyropoulus Method. It is about.

Recently, the research trend of sapphire substrate is progressing to improve the productivity of existing 2 inch and 4 inch wafers.

In addition, it is expected that 4 inch wafers will be applied to the process and will soon be replaced by 4 inch wafers. Ultimately, it is effective to increase the growth crystallization in order to suppress the small-angle angle and increase the utilization efficiency of the material. Inch wafers are expected to be applied to the process. For this purpose, in addition to the increase in size of single crystals, the size of growth devices has to be increased.

Sapphire is a crystal grown as a single crystal while alumina (Al ₂ O ₃ ) is melted at 2050 ° C. or more and is slowly cooled. Aluminum (Al) and oxygen (O) form a crystal structure of an HCP system (Rhobohedral system).

In general, sapphire is a single crystal of alumina, which has light transmittance in a wide range of wavelengths, and has excellent mechanical properties, heat resistance and corrosion resistance, as well as high hardness, thermal conductivity, electrical resistance, and large impact resistance.

Sapphire can also be used as an epitaxial growth substrate because it has no pores and a strong dielectric strength. In particular, it is recently used for a blue optical element substrate. To be used for this purpose, the crystal structure inside the crystal must be nearly gentle, i.e. free from internal defects.

Representative methods of growing sapphire single crystals include the Verneuil Method, the Heat Exchange Method, the Edge-Defined Film-Fed Growth, the Czochralski Method, and the Kyropoulus Method. Examples of crystal growth methods include the Czochralski method, the Heat Exchange Method, and the Kyropoulus Method.

The Kyropoulos method has the advantages of relatively low equipment cost and low production cost. It is very similar to the Czochralski method, but it does not rotate the single crystal but only raises it and has fewer defects than the boule grown by the Czochralski method. .

In the single crystal growth method using the same, alumina (Al ₂ O ₃ ), which is a raw material, is charged into the crucible, and the crucible is heated and melted above the melting point of alumina (Al ₂ O ₃ ) using a heating means, and then the seed (seed crystal) is used. The seed crystal is brought into contact with the surface of the melt by lowering the ingot rod decocted with), and it is pulled up by using a lifting means, and gradually cooled to below the melting point to obtain sapphire single crystal by using the phenomenon that alumina (Al ₂ O ₃ ) is solidified into a single crystal. do.

In order to cultivate single crystal sapphire using the Kiro Plus method as described above, a crucible and heating means that can be used above the sapphire melting temperature, a vacuum system capable of maintaining a high vacuum of 10 ^-3 torr or more, and a control means for winding ingots during single-crystal growth of large diameters In the process of single crystal growth, the overall construction means such as cooling means to maintain the temperature distribution evenly with precise temperature control should be complementarily optimized.

In the production of single crystals of compound semiconductors such as sapphire, polycrystallization and twinning control, which have a fatal effect on single crystal efficiency during growth, are very important variables and mass production is impossible without control.

However, the variables influencing this can be classified into temperature gradients, crucible materials and shapes, growth rates, composition ratios, impurity contents, materials and shapes of heat shielded scraps, and the like.

In addition, the degree of generation of defects also varies depending on the thermal conductivity, surface tension, and defect generation energy of the solid liquid, which are inherent physical properties of the material. However, the precise control is essential because the causes of polycrystals and twins, and their control methods, are not clearly identified in practice despite multiple analysis and models, and appear frequently during crystal growth.

 Among these, cooling means for maintaining the temperature distribution of the crucible and weighing means for accurately grasping the weight at the time of single crystal growth are the most important factors in order to obtain high quality sapphire single crystal.

The cooling means and the weighing means to which the prior art is applied are shown in Figs. 10 and 11, which are as follows.

The cooling means 1 to which the prior art is applied has a guide in the form of a thread (screw) in a single chamber 2, and an inlet 4 for supplying cooling water at the lower end of the chamber 2, The upper end is formed with an outlet 5 through which the coolant circulated can be discharged, and a coolant passage 14 through which the coolant can enter and exit is also formed in the ingot rod.

In this configuration, the cooling water is repeatedly supplied from the lower end of the chamber and discharged to the upper side after passing through the chamber in a spiral form, and thus the ingot surface inside the crucible is tensioned due to the formation of vertical temperature gradients between the upper and lower parts. The stress is induced and thus the compressive stress is applied inside.

Due to the thermal shock formed from such a temperature gradient, the dislocation defect density inside the ingot increases, which causes problems such as polycrystals and twins, which hinders single crystal growth and degrades single crystal quality.

The weighing means 10 to which the prior art is applied is provided with a load cell 13 at the lower end of the cantilever 12 protruding in the growth path direction at the upper end of the supporter 11.

In the prior art as described above, since the load acting on the cantilever and the stress and the weight of the ingot act simultaneously, a load cell capable of specifying a high load must be used so that the resistance does not appear only due to strain but changes slightly depending on temperature or humidity. Since it is practically impossible to measure the value, accurate load measurement is not possible, which also does not help to obtain a high quality single crystal sapphire ingot.

In the single crystal growth method using the prior art, the growth rate or shape of the ingot varies from time to time depending on the temperature range and convection form of the internal alumina (Al ₂ O ₃ ) melt until a single crystal ingot is obtained, and it depends on the sense of skilled technician. Therefore, it is difficult to continuously maintain excellent quality, and many problems occur such that automation systems using one or more growth devices are impossible.

Therefore, in the present invention, as the invention to solve the above problems, the growth furnace to maintain a high vacuum state, and the crucible is maintained as a crucible support to melt the raw material for forming the sapphire single crystal in the center of the growth furnace and And heating means for melting the supplied raw material by installing the outside of the crucible, cooling means installed on the outside of the heating means to diffuse and stabilize the heat distribution of the heating means and the crucible, and a supporter installed outside the growth furnace; And a lifting means capable of lowering and raising operation so as to wind up a single crystal grown ingot by installing on the supporter top, a cantilever projecting toward the center of the growth path from the upper side of the lifting means, and a driver connected to the cantilever beam. Is connected to the driver and mounted to the seed crystal at the bottom to rotate Extrusion ingot rod and, through the weight measurement of the single crystal is grown in the sapphire single crystal ingot growth apparatus comprising a weight measuring means for regulating the temperature, lifting and rotation speed;

The cooling means is composed of a double chamber to reduce the temperature difference of the upper and lower parts of the crucible, the weighing means using a plurality of load cells to precisely control the ingot of the growth stage by fine weight measurement of the excellent quality It is possible to achieve the purpose of mechanically repeating single crystal sapphire.

The present invention improves the cooling means and weighing means constituting the single crystal sapphire ingot growth apparatus to enable fine weight measurement while reducing the deviation of the temperature gradient to precisely control the growth of the ingot to obtain a good quality single crystal sapphire By increasing the quality of the growth device to improve the productivity it is an invention having various effects.

1 is a block diagram of a single crystal sapphire ingot growth apparatus shown to explain the present invention.
Figure 2 is a block diagram showing a crucible of the single crystal sapphire ingot growth apparatus shown for explaining the present invention.
Figure 3 is a view showing a process of growing a single crystal by the single crystal sapphire ingot growth apparatus shown to illustrate the present invention.
Figure 4 is a schematic view of the cooling means of the single crystal sapphire ingot growth apparatus to which the technique of the present invention is applied.
5 is a cross-sectional view showing the cooling means of the single crystal sapphire ingot growth apparatus shown in FIG.
Figure 6 is a block diagram showing another example of the cooling means of the single crystal sapphire ingot growth apparatus to which the technique of the present invention is applied.
Figure 7 is a block diagram showing another example of the cooling means applied to the single crystal sapphire ingot growth apparatus to which the technique of the present invention is applied.
Figure 8 is a block diagram showing the measuring means of the single crystal sapphire ingot growth apparatus to which the technique of the present invention is applied.
9 is a photograph showing sapphire single crystals grown by the technique of the present invention.
10 is a block diagram showing the cooling means of the single crystal sapphire ingot growth apparatus to which the prior art is applied.
Figure 11 is a block diagram showing the weighing means of the single crystal sapphire ingot growth apparatus to which the prior art is applied.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings.

1 is a configuration diagram of a single crystal sapphire ingot growth apparatus shown in order to explain the present invention, FIG. 2 is a configuration diagram showing a crucible of the single crystal sapphire ingot growth apparatus shown in order to explain the present invention, and FIG. 4 is a view illustrating a process of growing a single crystal by the single crystal sapphire ingot growth apparatus shown in order to explain, FIG. 4 is a schematic view of the cooling means of the single crystal sapphire ingot growth apparatus to which the technique of the present invention is applied, and FIG. 6 is a cross-sectional view showing a cooling means of the single crystal sapphire ingot growth apparatus shown in FIG. 6 is a block diagram showing another example of the cooling means of the single crystal sapphire ingot growth apparatus to which the technique of the present invention is applied, and FIG. Fig. 8 is a block diagram showing another example of cooling means applied to the applied single crystal sapphire ingot growth apparatus. Configuration showing the weight measuring means of the sapphire ingot growth apparatus, Fig. 9 will be described with a picture showing a sapphire single crystal grown by the technique of the present invention.

Single crystal sapphire ingot growth apparatus 100 is provided with a growth furnace 101 to be sealed with a heat insulating material to achieve a high vacuum state, and to fill and melt a raw material for forming sapphire single crystal in the inner center of the growth furnace 101. The crucible 102 is installed to be maintained by the crucible support 103.

The heating means 104 is installed outside the crucible 102 so as to melt the raw material supplied to the crucible 102, and the heating means 104 and the crucible 102 of the heating means 104 are installed outside the crucible 102. The cooling chamber CB provided outside the crucible 102 and the cooling means 105 are provided to form a cooling flow path CW so that the coolant can enter and exit the ingot rod so as to diffuse and stabilize the heat distribution.

On the upper end of the supporter 106 installed outside of the growth path 101, a lifting means 107 capable of lowering and raising operation such as a motor or a cylinder is installed so as to reel a single crystal grown ingot. .

The upper part of the lifting means 107 protrudes the cantilever 108 toward the center of the growth path 101, and the cantilever 108 is connected to a driver 109 such as a motor and rotates by mounting a seed crystal at a lower end thereof. Protrudes downward ingot rod 110 that can be.

Then, when the unitary growth, the weighing means 111 for measuring the lifting speed of the hoisting means 107, the rotational speed of the driver 109 and the weight of the grown single crystal for adjusting the temperature gradient of the crucible 102 It is equipped with.

In the present invention, by improving the cooling means 105 and the weighing means 111 constituting the growth device 100 to reduce the temperature variation of the crucible 102 according to the growth state of the ingot, and the lifting speed to the optimal state It is characterized in that to obtain a high quality single crystal sapphire ingot by adjusting.

The cooling means 105, the inner chamber 112 and the outer chamber 112 in close proximity to the crucible 102 and the cooling chamber (CB) provided in a cylindrical shape on the outside of the crucible (102) integrally It consists of the out chamber 113 formed.

Cooling water guide 114 is formed in the inner chamber 112 and the out chamber 113 to circulate the cooling water, and the coolant is supplied to the upper and lower sides of the inner chamber 112 and the out chamber 113. And inlet 115 and outlet 116 for over and discharge respectively.

The cooling water guide 114 formed in the inner and out chambers 112 and 113 is not formed at the same position, but is formed at a position shifted from each other so that the cooling water circulating the inner and out chambers 112 and 113 evenly forms the temperature of the crucible 102. To affect.

In addition, the inlet 115 and the outlet 116 formed in the inner chamber 112 and the out chamber 113 are also formed at positions opposite to each other. When the inner chamber 112 moves the coolant from the lower side to the upper side, the out chamber ( 113) takes the form of moving the cooling water from the upper side to the lower side so that the entire temperature distribution can be maintained without biasing the upper and lower portions of the crucible 102.

As another example of the cooling means 105, as shown in FIG. 6, the coolant of the inner chamber 112 can move helically, and the coolant of the out chamber 113 is zigzag in a straight line from the upper side to the lower side or the lower side to the upper side. It may be configured to be movable.

Of course, the cooling water of the out chamber 113 is moved helically, and the cooling water of the inner chamber 112 is configured to linearly move from the upper side to the lower side or the lower side to the upper side, or both the inner and the out chambers 112 and 113 are upward. It may be possible to allow the coolant to move zigzag in a straight line as opposed to the lower side.

As another example of the cooling means 105, a cooling water guide is formed on the lower surfaces of the inner and out chambers 112 and 113 so that the cooling water can be circulated, and supplying the cooling water to one side and the center of the lower surface. The inlet 115 and the outlet 116 are formed for the discharge, respectively, so that the coolant is spread in a spiral (scrolled form) so as to cool the entire bottom surfaces of the inner and out chambers 112 and 113.

The cooling means can act simultaneously or separately, and it was confirmed that precise temperature control at the lower end of the single crystal ingot growth through the present invention has a great influence on the quality of the single crystal.

When the Al ₂ O ₃ raw material melted by the heating means in the method for producing a single crystal according to the present invention is solidified by the cooling means,

｛(T1-T2) × m _s × Cs｝ + ｛(t1-t2) × m _w × Cw｝ + ｛m × Lf｝ ≤ 0

There is provided a single crystal growth apparatus characterized by controlling the mass flow rate (m _w ) of the cooling means to satisfy the relationship of.

The difference between the melt temperature (T1) and the melt temperature (T2) of the Al ₂ O ₃ raw material in the crucible (ΔT), the mass of Al ₂ O ₃ (m _s ), and the specific heat of Al ₂ O ₃ ( The total product of Cs) and the inlet temperature t1 of the cooling water flowing through the cooling means, the difference (Δt) of the outlet temperature t2 flowing through the cooling means, the mass flow rate of the cooling water (m _w ), the specific heat of the cooling water (Cw) The sapphire single crystal is ideally grown when the sum of the total product of and the latent heat ｛m × Lf｝ generated when the Al ₂ O ₃ melt is solidified satisfies the above equation.

In the present invention, the heat distribution of the crucible can be precisely controlled by controlling the flow rate of the cooling water flowing in the cooling means for the single crystal growth device to a certain range, whereby the temperature distribution inside the crucible is stabilized, and the thermal stress in the crystal Can be controlled or suppressed while achieving low dislocation density.

First, the present inventors control the flow rate of the cooling water passing through the cooling means of the single crystal growth apparatus to precisely discharge the amount of heat of the heated Al ₂ O ₃ melt in the crucible through the cooling means, which is more precise than the temperature control through the heating means. It is possible to create a uniform heat distribution diffusion, and vary the flow rate through the cooling means. A sapphire single crystal ingot without internal defects was obtained at 13.0 L / min.

The weighing means 111, by installing a large load cell 120 between the upper portion of the lifting means 107 and the cantilever 108 to measure the bending and tensile stress, and connected with the driver 109 A small capacity load cell 121 is installed between the ingot rods 110 to be used to measure the tensile stress according to the growth of the ingot, and the small capacity load cell 122 is provided in the crucible support 103 for maintaining the crucible 102. By installing a) it is configured to measure the compressive stress applied to the crucible support 103 as the molten melt (Melt) ingot growth in the crucible (102).

In order to accurately measure the melt temperature in the crucible 102, a temperature measuring means is installed in the hollow portion of the crucible support 103 to detect the actual temperature of the melt.

When the temperature measuring means is installed in close contact with the bottom of the crucible 102, the temperature measuring means is damaged due to high temperature, while maintaining a predetermined distance from the bottom of the crucible 102 to prevent damage to the temperature measuring means. It is desirable to minimize the error range of the temperature measurement.

As a result of this experiment, the temperature measuring means was placed at the bottom of the crucible 102 and 5? It has been shown that positioning within the range of 20 mm can minimize the measurement error range while preventing damage to the temperature measuring means.

In still another aspect of the present invention, the crucible 102 is composed of an internal crucible and an external crucible of the same shape so that the ingot can be grown at a more stable temperature gradient, and other conditions that can satisfy the crucible ( 102 is made of tungsten (W), iridium (Ir), tungsten-molybdenum (W-Mo), and tungsten-iridium (W-Ir).

Of course, it may be composed of any one material of tungsten (W), iridium (Ir), tungsten-molybdenum (W-Mo), tungsten-iridium (W-Ir), and an alloy combining at least one of these materials. The inner and outer crucibles 102 may be made of the same material.

Looking at the operation of the single crystal sapphire ingot growth apparatus 100 to which the technique of the present invention is applied as described above are as follows.

Sapphire single crystal growth process of the present invention is a Kyropoulos method, a melting step of melting the raw material filled in the crucible 102 with a heater, and a seeding step of contacting the seed crystal (seed) prepared on the surface of the melt; The necking process of raising the seed crystal at a constant speed to narrow the crystal until the predetermined diameter is formed, and the shoulder forming process of stopping the rise and growing the neck to the predetermined diameter to form the shoulder, and continuously It consists of a main body forming process that gradually drops the temperature to form the main body.

That is, alumina (Al ₂ O ₃ ), which is a raw material, is placed in the crucible 102 of the growth furnace 101, and then the heating means 104 is operated to be heated and dissolved above the melting point (2050 ° C.) of the alumina.

Then, the seed crystal (S) is mounted on the lower end of the ingot rod 110, and then the lifting means 107 in the ascending state is operated to bring the seed crystal (S) closer to the molten surface center position in the crucible (102). The seed crystals (S) are gradually brought into contact with the solution (Melt) or allowed to be partially immersed, and then placed in an appropriate position where the seed crystals do not melt from the solution in the crucible 102.

In this state, the temperature of the crucible 102 is adjusted to start the growth of the sapphire single crystal, and then, by appropriately adjusting the pulling speed, position, and temperature, a single crystal ingot of a shape close to a cylinder can be obtained.

In the present invention, the ingot weight change from the beginning to the end of the growth of the ingot is accurately sensed and measured through the weighing means 111, and the temperature of the melt inside the crucible 102 is located in the hollow of the crucible support 103 The temperature is measured by the temperature measuring means installed to maintain a predetermined interval with the bottom surface of the crucible 102 is applied to the controller (C).

The controller (C) precisely controls the flow rate of the cooling water flowing in the cooling means 105 according to the situation that the diameter of the ingot may be larger or smaller than the growth rate of the target program due to various factors during the growth of the ingot. Through the temperature of the crucible 102 is adjusted to an optimum state, and precise control of the coolant flow rate through the feedback from the weighing means and the temperature measuring means. Precision control can be controlled precisely through relief, butterfly or PCW systems, liquid regulators, inverters, and bypass systems.

In addition, by controlling the hoisting means 107 or the driver 109 to control at the optimum lifting speed or rotational speed so that the ingot of the target bar can grow.

The operation of the weighing means 111 detects the weight of the sapphire single crystal that changes in real time when the sapphire single crystal is grown from the Al ₂ O ₃ solution present in the crucible 102 in the liquid state.

That is, through the large-capacity load cell 120 installed in the lifting means 107 and the cantilever 108 senses a large weight, the ingot rod 110 connected to the other side driver 109 of the cantilever 108 Through the load cell 121 installed between the load cell 121 and the crucible support 103 is detected a small weight is applied to the controller (C).

The measurement principle of the load using the load cells (120, 121, 122) is a well-known technique for measuring strain by converting the amount of deformation into a load by measuring a small amount of deformation (resistance value) that decreases or increases when a strain gauge pulls or pushes an elastic body. Is omitted.

Bending and tensile stress of the cantilever 108 by the load cells 120, 121, and 122, tensile stress due to growth of the ingot, and compressive stress applied to the crucible support 103 as the melt (Melt) grows in the crucible 102. The measured value of is applied to the controller (C), and the various variables (ingot weight change, heater output change, temperature change, etc.) are comprehensively included through the fault diagnosis device included in the load cells (120, 121, 122). It is determined and applied to the controller (C) together.

In the controller C receiving the information, the cooling system 104, the lifting unit 107 and the driver 109 are not only controlled, but also a growth system composed of one or more growth apparatuses 100 is collectively. It will be natural to make it easy to control the data, or to make a database of measurement or control information for future management and design and installation of a new growth device.

As described above, the cooling means 105 under the control of the controller C moves the cooling water to effectively control the temperature of the crucible 102 and controls the driver 109 to rotate the ingot rod 110. In addition to the speed is to control the lifting speed of the lifting means (107).

Rotational speed of the ingot rod 110 controlled by the driver 109, the melt is convection in the crucible during the necking and shoulder forming process, the shoulder is non-uniform in accordance with the direction and speed of the convection during shoulder formation As the seed crystals are grown in the convective direction, it is necessary to proceed with the growing process while rotating the seed crystals that are appropriately grown in the convective direction. Do it.

At this time, the rotation speed of the driver 109 is 0? It is preferable to set in the range of 5 rpm, More specifically, 0? More preferably, the rotational speed is changed to accelerate or decelerate at a predetermined period set to 0.5 rpm.

As a result, in the process of forming the shoulder by properly rotating the seed during seeding in the Al ₂ O ₃ melt (Melt), a shoulder having a uniform shape can be formed over the entire range of the ingot.

Looking at the operation of the cooling means 105 in detail, the coolant is introduced through the inlet 115 of the inner chamber 112 is moved in a spiral or up and down, zigzag direction from the lower side to the upper side of the inner chamber 112 When discharged through the upper outlet 116, the coolant is supplied through the inlet 115 provided on the upper side of the out chamber 113 installed on the outer side of the inner chamber 112 in the downward direction of the out chamber 113. Since it is discharged through the lower exit 116 by moving in a spiral or up and down linear zig-zag, the inner and out chambers 112 and 113 can be controlled to maintain an even temperature without distinguishing the top and bottom of the crucible 102. Do.

In addition, since the coolant flows through the inlets and outlets further provided at the lower ends of the inner and out chambers 112 and 113 and circulates helically, the crucible support 103 which is in contact with the lower ends of the inner and out chambers 112 and 113 is referred to. As the edge of the crucible 102 is heated by the heater and the center is set at a relatively low temperature by the cooling means 105, the convection naturally gathers Al ₂ O ₃ melt (Melt) through it. By having a shape, it is possible to obtain a uniform ingot through the growth process.

Of course, if necessary, the inner chamber 112 or one of the out chambers 113 and the cooling means 105 installed on the lower end, or while operating the inner and out chambers 112, 113 at the same time cooling means 105 It will be natural to control while giving various changes depending on the state of the crucible 102, the growth state of the ingot, the hoisting state, etc.).

The present invention can grow the ingot at a stable temperature gradient by the improved cooling means provided in the crucible and the chamber consisting of a double, as well as the cooling means and winch through accurate weight measurement and temperature measurement from the beginning to the completion of growth By controlling the means and the driver mechanically (automated) in an optimal state, it is possible to obtain a single crystal sapphire ingot having a desired bar quality, and has the advantage of continuously repeatedly obtaining an ingot having excellent and uniform quality.

100; Growth device
101; Growing road
102; Crucible
105; Cooling means
107; Hoisting means
110; Ingot rod
111; Weighing means
112; Inner chamber
113; Out Chamber
120,121,122; Load cell

Claims (12)

A growth furnace 101 for maintaining a high vacuum state;
A crucible 102 maintained at the inner center of the growth furnace 101 as a crucible support 103 to melt raw materials for forming sapphire single crystals;
Heating means (104) installed outside the crucible (102) to melt the supplied raw material;
Cooling means 105 is installed outside the heating means 104 to diffuse and stabilize the heat distribution of the heating means 104 and the crucible 102;
A supporter (106) installed outside the growth path (101);
A lifting means (107) installed on an upper end of the supporter (106) and capable of lowering and raising operation to hoist a single crystal grown ingot;
A cantilever beam protruding from the upper portion of the lifting means 107 toward the center of the growth path 101;
A driver 109 connected to the cantilever 108;
An ingot rod 110 connected to the driver 109 and protruding downward so as to rotate by mounting a seed crystal at a lower end thereof;
In the single crystal sapphire ingot growth apparatus (100) comprising a weighing means (111) for adjusting the temperature, winch and rotational speed by measuring the weight of the single crystal to be grown;
The cooling means 105 includes an inner chamber 112 installed near the crucible 102 on the outside of the crucible 102;
Dual configuration with an outer chamber (113) formed integrally with the inner chamber (112) on the outside of the inner chamber (112);
Single inner sapphire ingot growth apparatus characterized in that the cooling water in the inner chamber 112 and the out chamber 113 is circulated to the opposite position to reduce the temperature difference of the upper and lower parts of the crucible (102). The method of claim 1, further comprising:
The weight measuring means 111 is installed between the upper portion of the lifting means 107 and the cantilever 108 to measure a large amount of load cell 120 and the bending stress;
A load cell 121 having a small capacity installed between the driver 109 and the ingot rod 110 connected to the ingot rod 110 to measure tensile stress according to growth of the ingot;
It is installed in the crucible butt holding the crucible 102 to include a small load cell 122 for measuring the compressive stress applied to the crucible butt 103 as the molten melt (Melt) ingot growth Single crystal sapphire ingot growth apparatus characterized in that. The method of claim 1, further comprising:
The cooling means 105, the lifting means 107 and the driver 109 are controlled by a controller (C) that receives the information of the weight measuring means 111 and the information of the temperature measuring means. Ingot growth device. The method of claim 1, further comprising:
The flow rate of the cooling water flowing through the cooling means 105 is 4.0? Single crystal sapphire ingot growth apparatus, characterized in that the control at 13.0 l / min. The method of claim 1, further comprising:
A cooling water guide 114 formed inside the inner chamber 112 and the out chamber 113 to allow the cooling water to circulate;
Single crystal sapphire ingot growth apparatus comprising an inlet 115 and an outlet 116 formed to supply and discharge the coolant to the upper and lower sides of the inner chamber 112 and the out chamber 113. The method of claim 1, further comprising:
The cooling water guide 114 and the inlet 115 and the outlet 116 formed in the inner and out chambers 112 and 113 have a coolant circulating in the inner and out chambers 112 and 113 evenly affecting the temperature of the crucible 102. Single crystal sapphire ingot growth apparatus, characterized in that formed in the position deviated from each other so as to maintain an even temperature distribution. The method of claim 1, further comprising:
The cooling means 105 has an inlet 115 and an outlet 116 at the lower ends of the inner and out chambers 112 and 113 to circulate the cooling water spirally to affect the temperature of the crucible 102 to maintain a uniform temperature distribution. Single crystal sapphire ingot growth apparatus, characterized in that to enable. The driver 109 is 0? So that a uniform shoulder portion can be made during ingot growth. Single crystal sapphire ingot growth apparatus characterized in that the speed can be changed and the rotation direction is changed at a set period within the range of 5rpm. The method of claim 1, further comprising:
The bottom of the crucible 102 and the bottom surface of the crucible 102 to minimize the measurement error range while preventing damage to the temperature measuring means A single crystal sapphire ingot growth apparatus, characterized in that it is possible to measure the temperature of the inner bottom of the crucible by placing the temperature measuring means within a range of 50 mm. The method of claim 1, further comprising:
The crucible (102) is a single crystal sapphire ingot growth apparatus, characterized in that the dual structure consisting of an inner crucible and an external crucible to grow the ingot at a stable temperature gradient. The method of claim 1, further comprising:
The crucible 102 is made of one or more alloys of tungsten (W), iridium (Ir), tungsten-molybdenum (W-Mo), tungsten-iridium (W-Ir) or one or more alloys. Sapphire Ingot Growth Device. The method of claim 10;
Single crystal sapphire ingot growth apparatus, characterized in that the inner crucible and the outer crucible is the same material.

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