JP4401524B2 - CZ method single crystal pulling equipment - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a CZ method single crystal pulling apparatus for pulling a single crystal from a raw material melt by the Czochralski method (hereinafter, CZ method). Further, the present invention particularly uses the dash neck method by adopting a dash neck method non-adopting type CZ method single crystal pulling apparatus, more specifically, by seeding a seed crystal in which the tip portion is heated and dissolved in advance into the raw material melt. CZ method single crystal pulling apparatus suitable for producing a dislocation-free silicon single crystal, and in particular, a CZ method single crystal pulling apparatus equipped with a mechanism suitable for preheating and melting the tip of the seed crystal About.
[0002]
[Prior art]
When the seed crystal is deposited on the raw material melt, dislocations (slip dislocations) are introduced into the seed crystal due to thermal shock at that time, and this dislocation is generally performed using the dash neck method. Excluded from seed crystals.
[0003]
Here, the dash neck method is a method of pulling up a seed crystal that has been deposited on a raw material melt and then narrowing the diameter of the seed crystal once (so-called seed squeezing). This is a method in which dislocations introduced into the seed crystal are directed toward the outer periphery of the crystal so as to eliminate dislocations, and the tensile strength of the seed crystal portion is reduced by the amount that the seed crystal is thinned by performing seed drawing.
[0004]
However, there is a fear that the stress applied to the dash neck portion may exceed the strength due to the recent increase in diameter of the pulling crystal and the accompanying weight increase, and a crystal falling accident may occur during pulling. For this reason, a method for growing a dislocation-free crystal without thinning the seed crystal portion has been studied.
[0005]
Against this background, it was first discovered that there was no introduction of dislocations only by dissolution and resolidification of the seed crystal, and a technology that applied this phenomenon to the FZ crystal method was accompanied by a reduction in the diameter of the seed crystal. The technology has been proposed as a technique for growing dislocation-free crystals without any modification (Japanese Patent No. 1257980).
[0006]
As a matter of course, this technique has been tried to be applied to the CZ method, and several application examples have been presented. Among them, typical examples of improved seed crystal tip melting methods are disclosed in WO97-32059 and JP-A-8-319192 using a laser to dissolve the seed crystal tip. US Pat. No. 5,885,344 discloses a method in which the tip of the seed crystal is dissolved using a resistance heater.
[0007]
Here, in the method using a laser, an expensive apparatus is required because the irradiation area of the laser is large, and the occupied space of the transmitter is large, so that it is not suitable for use in a mass production factory. For this reason, when considering use in a mass production factory, the method of melting the seed crystal tip using a resistance heating type heater is more suitable.
[0008]
However, in the case of the method of melting the seed crystal tip using a resistance heating type heater, the function of heating and melting the seed crystal by supplying electric power from outside the furnace, with the pulling crystal after the seeding step In order to avoid interference, a function for moving the heater and a control system for controlling these functions are required. How to solve this problem is that the resistance heating type heater is used for the tip of the seed crystal. This is a key point when adopting the method of melting.
[0009]
In this regard, although there is no detailed description of the function of moving the heater in US Pat. No. 5,885,344, in the embodiment, the rigidity that can expand and contract in the vertical direction in two steps from the inside of the upper vacuum chamber. It has been suggested that a resistance heater is attached to the vertical bar of the body, and the resistance heater is moved up and down by expansion and contraction of the vertical bar.
[0010]
However, if such a mechanism is adapted to the actual pulling operation, the resistance heater must also be raised with the growth of the crystal. Therefore, the movement width of the resistance heater is long enough for the crystal growth to be performed. In order to achieve this, it is necessary to adopt a configuration in which the vertical bar of the rigid body is expanded and contracted vertically in two or three stages as shown in FIG. As shown in FIG. 9, it must be configured to move in the vertical direction in one step.
[0011]
[Problems to be solved by the invention]
However, in both of the hypothetical methods shown in FIGS. 8 and 9, the electrode collar portion Q becomes long, the accuracy of the center position of the resistance heater 23 with respect to the seed crystal 13 is deteriorated, and the seed There is a problem that more power than necessary is required for melting the crystal tip, and uniform melting becomes difficult.
[0012]
Further, in the hypothetical method of FIG. 8, the resistance heater 23 must be raised in accordance with the growth of the single crystal 17, so the wire take-up drum must be moved up to a position where it does not interfere with the electrode flange portion Q. There is also a problem that the length of the wire 14 from the Si melt interface to the wire take-up drum becomes longer, which affects the resonance point of the crystal axis rotation and makes it difficult to grow a single crystal. This is the same in the hypothetical method of FIG. 9 and the upper chamber becomes larger in the axial direction, so the wire length from the Si melt interface to the wire take-up drum inevitably increases, The resonance point of crystal axis rotation is affected, and single crystal growth becomes difficult.
[0013]
Furthermore, both the hypothetical method of FIG. 8 and the method of FIG. 9 increase the size of the upper chamber both in the axial direction and in the circumferential direction, greatly increasing the cost of the apparatus. In addition, the height of the lifting room (clean room) must be increased, leading to an increase in overall cost and an increase in initial investment.
[0014]
In addition, in any of the systems shown in FIGS. 8 and 9, the sliding portion of the electrode flange portion Q is installed above the Si melt, and there is a problem that the number of contamination sources increases. Furthermore, since the resistance heater 23 remains on the crystal axis even after the seed crystal tip is dissolved, the flow path of the inert gas flowing from the upper part of the crystal axis is obstructed by the resistance heater 23, and the crystal axis There is also a concern that the gas flow will be uneven in the circular direction, which will greatly affect the quality and productivity of the single crystal.
[0015]
The present invention has been made in view of the problems as described above, and its purpose is to perform dislocation-free without using the dash-neck method by causing a seed crystal having a tip portion heated and dissolved in advance to land on a raw material melt. A CZ method single crystal pulling apparatus suitable for producing a silicon nitride single crystal, comprising a mechanism that can smoothly heat and dissolve a seed crystal tip by a resistance heater is provided. There is.
[0016]
[Means for Solving the Problems]
In order to achieve the above object, in the present invention, the shape of the resistance heater is a U shape surrounding the seed crystal, and after heating the tip of the seed crystal, it is retracted to a position where it does not interfere with the pulling crystal. The CZ method single crystal pulling apparatus is provided with a mechanism for moving the heater obliquely upward.
[0017]
More specifically, the present invention provides the following.
[0018]
(1) A CZ method single crystal pulling apparatus for producing a single crystal without using a dash neck method by causing a seed crystal in which the tip portion is heated and dissolved in advance to adhere to a raw material melt. A slanting direction moving device that is provided with a heating service member related to heating and melting and that is installed in the chamber through a chamber that houses various in-furnace items, and that moves the mounted heating service member in a slanting direction. A CZ method single crystal pulling apparatus comprising a direction moving device.
[0019]
The heating member may be any member as long as it relates to the dissolution of the tip of the seed crystal. Examples of such a member include a resistance heating body that performs heating by resistance heating and a raw material melt radiation light. Examples include a concave mirror that heats by condensing light. In addition, the single crystal produced without using the dash neck method according to the present invention is a silicon single crystal, in particular, a dislocation-free silicon single crystal having no slip dislocation as much as a silicon single crystal pulled using the dash neck method. It is a crystal.
[0020]
(2) The oblique movement device includes an arm body to which the heating service member is attached at an end thereof, and the arm body is disposed in the chamber with a predetermined oblique angle and maintains an airtight state. The CZ method single crystal pulling apparatus according to (1), wherein the chamber passes through the chamber while sliding.
[0021]
(3) The oblique direction moving device includes an arm body to which the heating service member is attached at an end thereof, a bridging member coupled to the arm body, a screw rod body screwed to the bridging member, A drive body for rotating a screw rod body, and the arm body is disposed in the chamber with a predetermined oblique angle and penetrates the chamber while sliding while maintaining an airtight state. (1) The CZ method single crystal pulling apparatus according to (1).
[0022]
(4) The oblique direction moving device includes a telescopic bellows member that covers a portion where the arm body penetrates the chamber and accommodates the arm body drawn out from the chamber. The CZ method single crystal pulling apparatus according to (2) or (3).
[0023]
(5) The CZ method single crystal pulling apparatus according to (4), further comprising an inert gas introduction hole for introducing an inert gas from an upper end of the bellows member.
[0024]
(6) The CZ according to any one of (2) to (4), wherein the heating service member attached to the end of the arm body is a resistance heating body for heating and dissolving the seed crystal. Single crystal pulling device.
[0025]
(7) The CZ method single crystal pulling apparatus according to (6), wherein the resistance heating body is U-shaped.
[0026]
(8) The heating service member attached to the end of the arm body is a heat beam reflector for condensing the seed crystal by condensing the heat beam emitted from the raw material melt onto the seed crystal. The CZ method single crystal pulling apparatus according to any one of (2) to (4).
[0027]
(9) The CZ method single crystal pulling apparatus according to (8), wherein the heat ray reflector is a concave mirror.
[0028]
(10) The CZ method single crystal pulling apparatus according to (6) or (9), comprising two or more oblique movement devices.
[0029]
In addition, the present invention can basically be grasped as the following method.
(11) A moving device for moving the heating means for heating the seed crystal in the CZ furnace, and capable of retracting the heating means to a position where it does not interfere with the single crystal pulled from the raw material melt. A method of converting to a CZ method single crystal pulling apparatus that does not employ the dash neck method, with almost no modification of the current CZ method single crystal pulling apparatus, by attaching the moving device to the current CZ method single crystal pulling apparatus .
[0030]
Furthermore, the present invention can be applied not only to a CZ method single crystal pulling apparatus that does not employ the dash neck method but also to a normal CZ method single crystal pulling apparatus that employs the dash neck method. And the structure of such an apparatus is as follows, for example.
[0031]
(12) A CZ method single crystal pulling apparatus for pulling a single crystal from a raw material melt by the Czochralski method (CZ method), various in-furnace products for pulling a single crystal from the raw material melt, and the raw material A chamber that houses the melt and the various in-furnace items inside and isolates them from the outside, and the chamber is an oblique movement device that is provided in the chamber through the chamber, The various furnace internal members attached to the end are moved in an oblique direction to the position where the single crystal being pulled does not interfere with the pulling of the single crystal. A CZ method single crystal pulling apparatus, comprising a slanting direction moving apparatus capable of retracting a material.
[0032]
Here, “a position that does not interfere with the pulling of the single crystal with respect to the pulled single crystal” means that the physical interference such as a collision with the pulled single crystal such as a shoulder portion of a so-called chamber. It means the position that does not cause. In addition, “can be retracted” means that there is a possibility that it can be moved to the “position where it does not interfere with the pulling of the single crystal with respect to the pulled single crystal” although it moves in the oblique direction. It means that you are prepared.
[0033]
In addition, each structure shown in said (1)-(10) is suitably employable also with respect to the normal CZ method single crystal pulling apparatus which employ | adopts such a dash neck method. In this case, the specific oblique direction moving devices shown in (2) to (5) above can be employed in the same forms as shown in (2) to (5) above. Further, as in the above (6) and (7), it is also possible to attach a resistance heating body as various in-furnace members attached to the end as in (8) and (9). In addition, a heat ray reflector can be attached as various furnace members. In such a case, the temperature of the predetermined portion of the single crystal is increased by the heating by the resistance heater or the reflected light from the heat ray reflector, thereby appropriately adjusting the temperature of the predetermined portion of the single crystal. And the flexibility of adjusting the temperature gradient of the single crystal is increased.
[0034]
Furthermore, even in a normal CZ method single crystal pulling apparatus that employs the dash neck method, it is of course possible to include a plurality of oblique movement devices as in (10) above.
[0035]
BEST MODE FOR CARRYING OUT THE INVENTION
FIG. 1 is a block diagram showing an overview of the entire CZ method single crystal pulling apparatus according to the present invention.
[0036]
As shown in FIG. 1, in the CZ method single crystal pulling apparatus according to the present invention, the crucible 11 for storing the raw material melt and the seed crystal attached to the end, as in the normal CZ method single crystal pulling apparatus. A wire 14 that freely moves 13 in the vertical direction is accommodated in the chamber 15. The actual CZ method single crystal pulling device includes a heater for heating the crucible 11, a lifting device for moving the crucible 11 up and down, and a heat shield that shields heat radiation from the melt on the pulled single crystal. In addition, a cooler and other in-furnace members for cooling the pulled single crystal are accommodated, but these members are not shown in each drawing of the present specification for ease of explanation. .
[0037]
In the CZ method single crystal pulling apparatus according to the present invention, like the ordinary CZ method single crystal pulling apparatus, the inside of the chamber 15 is decompressed to a vacuum state, and the single crystal is pulled up from the raw material melt in that state. As a characteristic configuration, the oblique movement device 20 is attached to the outer wall of the chamber 15.
[0038]
In this embodiment, the direction moving device 20 includes an arm body 21 that penetrates the outer wall of the chamber 15 while sliding in an airtight state. A resistance heating body 23 is attached, and the distal end portion of the seed crystal 13 is heated and dissolved by the resistance heating body 23 so that the heat-dissolved seed crystal is deposited on the raw material melt 16. Since the seed crystal dissolved by heating in this way is deposited on the raw material melt 16, dislocation does not run in the seed crystal due to thermal shock at the time of liquid deposition. There is no need to perform an operation that eliminates.
[0039]
Here, in the CZ method single crystal pulling apparatus according to the present invention, heating is performed in a state where the resistance heating body 23 surrounds the tip portion of the seed crystal 13, and the tip portion of the seed crystal 13 is heated and melted ( 1A), after the tip of the seed crystal 13 is sufficiently heated and melted by the resistance heating body 23, the arm body 21 slides obliquely upward and retracts to a position that does not hinder the pulling of the single crystal. (FIG. 1B).
[0040]
As described above, in the CZ method single crystal pulling apparatus according to the present invention, since the oblique movement device 20 for moving the resistance heater 23 in the oblique direction is attached to the outer wall of the shoulder portion of the chamber 15, the seed crystal After the heat treatment of the tip portion, the resistance heating body 23 can be retreated to a position where it does not hinder the pulling of the single crystal in the CZ furnace, and different from the apparatus as shown in FIGS. The chamber 15 is not expanded in the vertical and horizontal directions, which is very advantageous in terms of cost.
[0041]
Furthermore, since the oblique direction moving device 20 can be attached to an existing CZ method single crystal pulling device, it is preferable in terms of maintenance and use of existing facilities. In addition, when attaching to the existing CZ method single crystal pulling apparatus, it can attach using the observation window etc. which were provided in the normal CZ method single crystal pulling apparatus. In addition, as shown in FIG. 4, it is also possible to attach a plurality of oblique movement devices 20 using a plurality of observation windows or the like that are normally provided.
[0042]
Next, the configuration of the oblique direction moving device 20 will be described in detail. As already described, the resistance heating body 23 is attached to the tip of the arm body 21 of the oblique direction moving device 20, but FIG. As shown, the other end of the arm body 21 protrudes outside through the chamber 15. The other end of the arm body 21 is connected to a bridging member 24, and the bridging member 24 is screwed to the screw rod body 25. Further, the screw rod body 25 is rotated by the driving force of the motor 26, and when the screw rod body 25 rotates, the bridging member 24 is moved in the axial direction of the screw rod body 25 accordingly. As a result, the arm body 21 is pulled out of the chamber 15 or pushed into the chamber 15 in conjunction with the movement.
[0043]
Here, since the arm body 21 is set to be inclined, when the arm body 21 is pushed into the chamber 15, the resistance heating body 23 is inclined to a position where the resistance heating body 23 surrounds the seed crystal 13. When the arm body 21 is pulled out from the chamber 15 while moving downward in the direction, the resistance heating body 23 can move upward in an oblique direction to a position that does not hinder the pulling of the single crystal 17.
[0044]
In particular, the resistance heating body 23 moves upward in an oblique direction and is finally stored under the shoulder portion of the chamber 15, and does not become an obstacle when the single crystal 17 is pulled up. It is a promising effect based on what is set to. In addition, since the arm body 21 is set obliquely, the portion through which the arm body 21 penetrates the chamber 15 is not positioned directly above the crucible 11, so that the arm body 21 slides at the penetration portion of the chamber 15. Even when the above is repeated, the risk that the portion becomes a contamination source for the crucible is remarkably reduced.
[0045]
The portion through which the arm body 21 penetrates the chamber 15 has a sliding structure in which the airtightness is maintained. However, in order to ensure the airtightness, the CZ method single crystal pulling apparatus according to the present invention. , The arm body 21 covers a portion penetrating the chamber 15 and is provided with a bellows member 27 for storing an exposed portion of the arm body 21 drawn out from the chamber 15. Then, an inert gas such as argon is appropriately supplied to the inside of the bellows member 27.
[0046]
Here, FIG. 2 is a view for explaining the configuration of the resistance heating body 23 attached to the tip end portion of the arm body 21 of the oblique direction moving device 20. As shown in FIG. 2, the resistance heating body 23 attached to the distal end portion of the arm body 21 includes electric wires 23a and 23b and a resistance heating section 23c. The shape of the resistance heating section 23c is an arc shape. Or it is U-shaped.
[0047]
The reason for this shape is that if the resistance heating portion 23c is circular when it moves obliquely upward after the seed crystal 13 is heated, the seed crystal 13 becomes in the way and cannot move. It is. That is, by making the resistance heating part 23c arcuate or U-shaped, when the resistance heating body 23 moves obliquely upward, the seed crystal 13 passes through the notched portion, so that smooth movement is possible. Become.
[0048]
Here, the shape of the resistance heating unit 23c will be further described. In order to sufficiently and uniformly heat the tip portion of the seed crystal 13, the shape of the resistance heating unit 23c is basically a shape surrounding the seed crystal 13. However, the U-shaped shape as shown in FIG. 2B is preferable from the viewpoint of sufficient and uniform heating of the tip portion of the seed crystal 13 rather than the small arc shape as shown in FIG. 2A.
[0049]
In addition, in the case of a semicircular arc shape as shown in FIG. 2C, in the case of a CZ method single crystal pulling device provided with two oblique movement devices 20 as shown in FIG. The resistance heaters 23 respectively extending from the oblique direction moving device 20 can be integrated into a perfect circle at the portion where the tip portion of the seed crystal 13 is heated and melted.
[0050]
Next, an embodiment of the oblique movement device 20 will be described in more detail. FIG. 3 illustrates a detailed configuration of the oblique movement device 20 according to a preferred embodiment of the present invention. FIG. 3A is a side view, FIG. 3B is a cross-sectional view taken along line AA in FIG. 3A, and FIG. FIG. 3D is a top view and FIG. 3D is a BB cross-sectional view of FIG. 3C.
[0051]
First, as shown in FIGS. 3A and 3B, in the oblique direction moving device 20 according to the preferred embodiment, the bellows upper end flange 24 ′ with respect to the screw rod body 25 that moves the arm body 21 in the length direction. (Member corresponding to the bridging member 24) is not only screwed at the end 24′a, but also a guide rail 31 and a guide block 33 for guiding the moving direction of the bellows upper end flange 24 ′. Is provided.
[0052]
Further, as shown in FIG. 3A, in the oblique movement device 20 according to the preferred embodiment, the positioning accuracy of the resistance heating body 23 is prevented from being misaligned due to the thermal expansion of the arm body 21, and the accurate temperature control is performed. Although cooling water is passed for the purpose of preventing overheating of the apparatus itself, as shown in FIGS. 3C and 3D, in the preferred embodiment, cooling water pipes 34a and 34b for passing cooling water are respectively double pipes. In addition, the cooling water is supplied from the inside of the double pipe and the cooling water is discharged from the outside.
[0053]
By adopting such a structure, since the supplied cooling water is supplied while being shielded by the discharged cooling water, the cooling effect is improved. In this preferred embodiment, power cables 35a and 35b for supplying power to the resistance heating unit 23c via the electric wires 23a and 23b are connected to the cooling water pipes 34a and 34b, respectively. 34b and the bellows upper end flange 24 'are insulated by insulating materials 36a and 36b.
[0054]
5 and 6 are views showing a CZ method single crystal pulling apparatus including two oblique movement apparatuses according to another embodiment of the present invention. In addition, the same code | symbol is attached | subjected to the component same as the component shown by FIGS. 1-4, and the description is abbreviate | omitted.
[0055]
In the oblique movement device according to another embodiment shown in FIG. 5, a concave mirror is attached to the distal end portion of the arm body 21. Here, assuming that the pair of oblique movement devices according to this embodiment are 120a and 120b, and the concave mirrors attached to the tip portions of the arm bodies are 40a and 40b, respectively, they are shown in FIGS. 6A and 6B. As described above, when the concave mirrors 40a and 40b are combined and integrated, a single concave concave mirror body 40 is formed.
[0056]
Here, as shown in FIG. 6, the concave mirrors 40 a and 40 b are provided with a hole 41 for taking in the seed crystal 13, and the concave mirrors 40 a and 40 b form one curved concave mirror body 40. When this is done, the radiation light from the raw material melt is collected so as to be focused at a predetermined location.
[0057]
In the oblique movement apparatus according to the present embodiment having such a configuration, the seed crystal 13 is lowered until the tip portion of the seed crystal 13 is located at the focal point of the concave mirror body 40, and then obliquely from above. The concave mirrors 40a and 40b are moved obliquely downward to form one curved concave mirror body 40, respectively. When one curved concave mirror 40 is formed, the tip of the seed crystal 13 is focused as shown in FIG. 6D, so that the tip of the seed crystal 13 can be dissolved. it can. Thereafter, as in the case of the resistance heater, the dissolved seed crystal is deposited on the raw material melt, and the single crystal is pulled up in accordance with a normal CZ method processor.
[0058]
In the above embodiment, the case where the present invention is applied to a dash neck method non-adopting type CZ method single crystal pulling apparatus has been described, but the present invention is a normal type CZ employing the dash neck method. It can also be applied to a process single crystal pulling apparatus.
[0059]
FIG. 7 is a view showing an embodiment in which the present invention is applied to a normal type CZ method single crystal pulling apparatus that employs the dash neck method. A body 50 is attached. The arm body 21 is a part of the oblique movement device 20 that has already been described, and the other end is connected to each member of the oblique movement device 20 (not shown).
[0060]
Then, as apparent from FIG. 7, after the seed crystal 13 is deposited on the raw material melt 16 and the seed crystal is squeezed, when the single crystal 17 is pulled up from the raw material melt 16, the shoulder portion of the single crystal 17 is In the protruding state (FIG. 7A), the shoulder portion of the single crystal 17 is heated by the reflected light from the flat reflector 50.
[0061]
And if the single crystal 17 is pulled up to some extent, the flat reflector 50 will retract | save in the diagonal direction according to it. Then, the side surface of the single crystal 17 is heated by the reflected light at a position where it does not interfere with the pulling of the single crystal 17, thereby contributing to the adjustment of the temperature gradient of the single crystal side surface. As described above, the obliquely moving device 20 according to the present invention can be used as a tool for moving a necessary in-furnace member even in a normal type CZ method single crystal pulling device adopting the dash neck method. .
[0062]
【The invention's effect】
According to the present invention as described above, since the in-furnace member of the CZ method single crystal pulling apparatus can be easily moved in an oblique direction, it can be moved to a position that does not hinder crystal pulling. .
[0063]
In addition, according to the present invention, by simply installing the oblique movement device, the present CZ method single crystal pulling apparatus is converted into a CZ method single crystal pulling apparatus that does not adopt the dash neck method, with little modification. The initial cost for manufacturing the CZ method single crystal pulling apparatus that does not employ the dash neck method can be reduced, and the modification stop period of the apparatus can be minimized. .
[0064]
The dash neck method non-adopting type CZ method single crystal pulling apparatus to which the present invention is applied particularly has the following significant effects.
[0065]
When the seed crystal needs to be heated and dissolved, the heating service member descends diagonally downward, while when the seed crystal is heated and melted, it moves diagonally upward and does not hinder the pulling of the single crystal. Therefore, the seed crystal can be heated and dissolved smoothly and the single crystal can be pulled up smoothly.
[0066]
Since the presence of the resistance heater does not affect the wire length from the Si melt interface to the wire take-up drum, the resonance point of crystal axis rotation does not shift, and the single crystal growth parameters are changed depending on the presence or absence of the resistance heater. It does not have to be. In addition, the drive source is outside the furnace, resulting in a system that minimizes dust generation, and the presence of the resistance heater does not affect the crystal length that can be raised.
[0067]
Since the electrode flange (arm body) is cooled and inclined, the length thereof can be minimized, so that the center position accuracy of the resistance heater is good even at high temperatures.
[0068]
Since a hose is not installed in the furnace for cooling the electrode flange, it is possible to provide a system that is less susceptible to steam explosions.
[0069]
After the resistance heater melts the tip of the seed crystal, it exists away from the seed crystal axis, and the flow path of the inert gas flowing from the upper part of the pulling shaft is not obstructed by the resistance heater, and the circle of the pulling crystal is Uniform gas flow can be provided in any direction, without affecting the quality and productivity of the pulled crystal.
[Brief description of the drawings]
FIG. 1 is a block diagram showing an outline of an entire CZ method single crystal pulling apparatus according to the present invention.
FIG. 2 is a diagram for explaining a configuration of a resistance heating body 23 attached to a tip portion of an arm body 21 of the oblique direction moving device 20;
3 illustrates a detailed configuration of an oblique movement device 20 according to a preferred embodiment of the present invention, FIG. 3A is a side view, FIG. 3B is a cross-sectional view taken along line AA in FIG. 3A, and FIG. 3D is a cross-sectional view taken along the line BB in FIG. 3C.
FIG. 4 is a diagram showing an embodiment of a CZ method single crystal pulling apparatus to which two oblique movement devices 20 are attached.
FIG. 5 is a diagram showing a CZ method single crystal pulling apparatus including two oblique movement devices according to another embodiment of the present invention, and is a block diagram showing an outline of the entire CZ method single crystal pulling apparatus. .
6 is a view showing a CZ method single crystal pulling apparatus including two oblique movement apparatuses according to another embodiment of the present invention, and is a view for explaining a functional configuration of a concave mirror body 40. FIG. 6A is a top view illustrating how the two concave mirrors 40a and 40b approach each other, FIG. 6B is a top view illustrating a state where the two concave mirrors 40a and 40b are combined, and FIG. FIG. 6D is a cross-sectional view for explaining how the seed crystal tip portion is heated and dissolved by condensing the radiant light from the raw material melt at the focal point, and showing a state in which the concave mirrors 40a and 40b are integrated. FIG.
FIG. 7 is a diagram showing an embodiment in which the present invention is applied to a normal type CZ method single crystal pulling apparatus employing a dash neck method.
FIG. 8 is a diagram illustrating a moving mechanism of a resistance heater hypothesized from the diagram shown in US Pat. No. 5,885,344.
FIG. 9 is a diagram illustrating a moving mechanism of a resistance heater hypothesized from the diagram shown in US Pat. No. 5,885,344, and illustrates a moving mechanism according to a form different from that shown in FIG. FIG.
[Explanation of symbols]
11 crucible
13 seed crystals
14 wires
15 chambers
16 Raw material melt
17 Single crystal
20 Oblique direction moving device
21 Arm body
23 Resistance heating element
23a and 23b electric wire
23c Resistance heating unit
24 Cross-linking member
24 'Bellows top flange
24a 'end of bellows upper end flange 24'
25 Screw rod
26 Motor
27 Bellows member
31 Guide rail
33 Guide block
34a and 34b cooling water pipes
35a and 35b Power cable
36a and 36b insulation
120a and 120b A pair of oblique movement devices
40a and 40b concave mirrors
40 One concave concave mirror
41 Hole for taking in seed crystal 13
50 Flat reflector

Claims (6)

A CZ method single crystal pulling apparatus for producing a single crystal without using the dash neck method by bringing a seed crystal in which the tip is heated and dissolved in the inside of the chamber into a raw material melt and pulling up the single crystal Because
Includes an oblique direction moving device provided in the outer wall of the shoulder portion of the chamber through said chamber,
The oblique direction moving device has a heating service member that heats and melts the tip of the seed crystal , moves the heating service member in an oblique direction with respect to the pulling direction of the single crystal ,
The heating in service member, CZ method single crystal pulling apparatus, characterized by have a resistive heating element state heating of U-shaped or arc-shaped capable of the tip and surrounds the seed crystal. The oblique movement device includes an arm body to which the heating member is attached at an end thereof,
2. The CZ according to claim 1, wherein the arm body is disposed inside the chamber with a predetermined oblique angle and penetrates the chamber while sliding while maintaining an airtight state. Single crystal pulling device. The oblique direction moving device includes an arm body to which the heating service member is attached at an end thereof, a bridging member coupled to the arm body, a screw bar body screwed to the bridging member, and the screw bar body And a driving body for rotating the
2. The CZ according to claim 1, wherein the arm body is disposed inside the chamber with a predetermined oblique angle, and penetrates the chamber while sliding while maintaining an airtight state. Single crystal pulling device.   The oblique movement device includes a telescopic bellows member that covers a portion of the outer wall of the chamber through which the arm body passes and accommodates the arm body that has been drawn out from the chamber. Item 4. The CZ method single crystal pulling apparatus according to Item 2 or 3.   5. The CZ method single crystal pulling apparatus according to claim 4, wherein the bellows member has an inert gas introduction hole for introducing an inert gas from an upper end thereof.   The CZ method single crystal pulling apparatus according to claim 1, further comprising two or more oblique movement apparatuses.

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