JP2665500B2 - Wire steadying device for CZ furnace - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a wire steadying device of a CZ furnace for preventing lateral deflection of a wire supporting single crystal silicon in the CZ furnace.

(Prior art) In recent years, the capacity of CZ furnaces has been increased, and therefore, the seed crystal is not easily affected by micro-vibration and the furnace height can be set low. CZ to produce single crystal silicon by raising the generated single crystal silicon while rotating and winding the wire
Furnace is mainly used.

In such a CZ furnace 1, as shown in FIG. 3, a crucible 3 is provided in a CZ furnace chamber 2 so as to be rotatable by a motor or the like. In the figure, 4 is a silicon melt in the crucible 3, 5 is a wire hanging down toward the center of the crucible 4, 7 is a seed crystal attached to the lower end of the wire via the chuck 6, 8 is a seed crystal 7 Single crystal silicon that grows by adhering.

Further, a wire steadying device 10 is provided on the upper wall 2a of the CZ furnace chamber 2 in order to prevent the quality and shape of the single crystal from being deteriorated due to the swing. As shown in FIG. 4, the wire steadying device 10 includes a flange 11 attached to the upper wall 2a, a rod 12 penetrating through insertion holes 2A, 11A provided in the upper wall 2a and the flange 11, Rod 12
And a fixing member 15 for fixing the rod 12 with the screw 14. An operation handle 16 is attached to an outer end of the rod 12, a guide jig 17 is attached to an inner end of the rod in the upper wall, and a viewing window 18 is provided in a direction perpendicular to the rod insertion portion. By grasping the operation handle 16 while monitoring from the viewing window 18 and moving the rod 12 in the axial direction, the guide jig 17 is brought into contact with the wire 5, thereby suppressing the lateral deflection of the wire 5 and improving the quality of single crystal silicon. Is being planned.

(Problems to be Solved by the Invention) However, according to the conventional wire steadying device,
There is a drawback that the positioning accuracy of the wire must be lowered due to manual operation and errors in the processing accuracy of the parts.

Further, since the manual operation is performed by bringing the guide jig into contact with the wire, there is a problem that the swing width is increased depending on the operation, and there is a problem that skill is required. Furthermore, in order to avoid interference with the guide jig when lifting and lowering the chuck,
There was a disadvantage that the wire steady rest had to be released on the way. Further, there is a possibility that foreign matter is generated and dropped into the single crystal silicon due to contact wear between the wire and the guide jig.

Therefore, in the present invention, the above-described problem is solved by performing the steady rest on the wire in a non-contact manner, and the steady rest can be performed over the entire range from the start to the completion of the manufacturing process. It is intended to provide a stop device.

(Means for Solving the Problems) The wire steadying device according to the present invention comprises a crucible containing a silicon melt placed in a CZ furnace, and a crucible having a seed crystal attached to a tip thereof through a chuck. A CZ furnace that hangs down toward the center of the seed crystal to produce single crystal silicon by adhering and growing on the seed crystal. It is arranged so as to be able to move up and down, and is configured to prevent the wire from swaying due to non-contact by electromagnetic force.

(Operation) When an electromagnet generates an electromagnetic force of the same polarity as the magnet, the magnetic force between the electromagnet and the magnet surrounded by the electromagnet repels, thereby restricting the wire from touching. In addition, by raising the electromagnet in response to the rise of the wire, the touch of the wire can be suppressed over the entire range of the single crystal silicon generation process.

Embodiment An embodiment of the present invention will be described below with reference to the drawings.

FIG. 1 is a schematic diagram showing a CZ furnace 21 during single crystal silicon growth. In FIG. 1, reference numeral 22 denotes a CZ furnace chamber, and 23 denotes a CZ furnace.
A crucible disposed rotatably by a motor or the like in the furnace chamber 22, 24 is a silicon melt in the crucible 23, 25 is a wire suspended toward the center of the crucible 23, and 27 is a lower end of the wire 25. The seed crystal 28 attached via the chuck portion 26 is a single crystal silicon that grows by attaching to the seed crystal 27.

A winder (not shown) is provided above the chamber 22 for rotating and winding the wire as shown by the arrow in the figure. Crystalline silicon 28 is generated.

Further, a wire steadying device 30 is provided on the chamber upper wall 22a. That is, as shown in FIG. 2, a permanent magnet 31 is attached to the upper part of the chuck portion 26,
An electromagnet 32 is provided around the permanent magnet 31 at a predetermined interval. This electromagnet 32 is formed in a disk shape,
A plurality of guide shafts 33 arranged in the upper and lower direction in the upper wall 22a of the chamber 22 are supported via set jigs 34 so as to be vertically movable. The set jig 34 is inserted into each guide shaft 33, and a sliding member 35 that slides on the guide shaft 33 is attached to the upper and lower surfaces thereof. Therefore, appropriate friction is provided between the guide shaft 33 and the sliding contact member 35, and the electromagnet 32 can be moved in the vertical direction along the guide shaft 33. 32 can be supported.

The lower end of a spring-shaped cable 36 is attached to the upper part of each set member 34. The upper end of this cable 36 is attached to a hoist (not shown), and the electromagnet 32 is moved upward by the permanent magnet 31. It is structured to be able to rise with. Further, the electromagnet 32 is connected to an external controller 38 through a lead wire 37 so that the electromagnet 32 generates an electromagnetic force having the same polarity as that of the permanent magnet 31 so that the permanent magnet 31, that is, the wire 25 is prevented from swaying. ing. And
The controller 38 controls the electromagnet 32 according to the amount of deflection of the wire 25.
The structure can reduce the electromagnetic force generated.

According to such a wire steadying device, the permanent magnet 31 attached to the chuck 26 is set at the lowermost end in accordance with the single crystal silicon generation process, and the position of the electromagnet 32 is set correspondingly. When the winder is driven, the permanent magnet 31 rises while rotating with the wire 25 in accordance with the production process. On the other hand, the electromagnet 32
Is moved up along the guide shaft 33 in accordance with the rise of the permanent magnet 31. Therefore, even if the permanent magnet 31 attempts to oscillate laterally in response to the deflection of the wire 25, a repulsive force acts between the permanent magnet 31 and the electromagnet 32 due to the electromagnetic force of the electromagnet 32, and the lateral oscillation of the permanent magnet 31 is reduced. As a result, the deflection of the wire 25 is reduced. In addition, the electromagnet 32 depends on the amount of deflection of the wire 25.
Since the generated electromagnetic force is adjusted by the controller 38,
Even if the amount of deflection is large, it is possible to reliably prevent the deflection of the wire.

(Effects of the Invention) As described above, according to the present invention, since the deflection of the wire is suppressed by non-contact using the electromagnetic force, the operation does not require skill as in the related art, and each component of the device is not required. The influence of machining accuracy and mounting accuracy is small, and furthermore, steady rest control can be performed over the entire range of the production process. Furthermore, since there is no contact, there is no generation of foreign matter due to abrasion. Therefore, no foreign matter is mixed into the generated single crystal silicon, and quality can be improved.

[Brief description of the drawings]

1 and 2 show an embodiment of the present invention, and FIG.
FIG. 2 is a schematic sectional view of a CZ furnace, FIG. 2 is an enlarged sectional view of a main part showing a steady rest device, FIGS. 3 and 4 show a conventional example, and FIG.
FIG. 4 is a schematic sectional view of the CZ furnace, and FIG. 4 is an enlarged sectional view of a main part of the steady rest device. 21 ... CZ furnace, 23 ... Crucible 24 ... Silicon melt, 25 ... Wire 26 ... Chuck, 27 ... Seed crystal 28 ... Single crystal silicon 30 ... Wire steadying device 31 ... Magnet, 32 ... electromagnet

Claims (1)

(57) [Claims] 1. A crucible containing a silicon melt is placed in a CZ furnace, and a wire having a seed crystal attached to a tip thereof through a chuck portion is dropped toward the center of the crucible, and adheres and grows on the seed crystal. In a CZ furnace that produces single-crystal silicon, a magnet is attached to the chuck portion, and an electromagnet surrounding the magnet at predetermined intervals is arranged so as to be vertically movable,
A wire sway preventing device for a CZ furnace, wherein the wire is prevented from swaying by non-contact due to electromagnetic force.