JPH11199372A - Apparatus for pulling up single crystal, device for preventing drop and method therefor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an apparatus for pulling up a single crystal not requiring delicate winding control for correcting elongation of a wire in good balance, and addition of center-controlling structure, further not requiring high building and bellows having a long length and a large outer diameter to design to reduce cost and to make the apparatus and the building compact. SOLUTION: A seed crystal-holding member 11 holding a seed crystal 12 is lowered by a first lifting and lowering means 13 to a molten liquid-contacting position at which the seed crystal 12 is brought into contact with the molten liquid 5. The seed crystal-holding member 11 is lifted at least in or at a stroke from the molten liquid- contacting position to an engaged part-forming position at which an engaged part 8 is formed on a single crystal 6 by the first lifting and lowering means 13. At the position, an engaging member 17 hung by a single rope-like body 15 and capable of engaging with the engaged part 8 is lowered by a second lifting and lowering means 20 to the engaged part-forming position so as to engage with the engaged part 8. The engaging member 17 is lifted by the second lifting and lowering means 20 by winding up the single rope-like body 15 within a stroke from the engaged part- forming position to the position finishing the pulling up of the single crystal 6.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a single crystal pulling apparatus or single crystal pulling apparatus used for growing a single crystal by bringing a seed crystal into contact with a melt and then pulling the seed crystal from the melt. The present invention relates to a fall prevention device for preventing a fall at the time, and a method for raising and dropping the same.

[0002]

2. Description of the Related Art With the recent development of VLSI, there is a demand for cost reduction in the manufacture of VLSI. In order to realize this cost reduction, it is essential to increase the diameter of the silicon wafer. In order to efficiently collect a large number of large-diameter wafers, a semiconductor silicon single crystal is formed by a so-called Czochralski method (C
It has been found that when a single crystal is pulled and grown by the Z method), the larger the crystal diameter and the longer the crystal diameter, the better.

However, it is premised that high-quality single crystals without dislocations are pulled and grown.

[0004] For this purpose, usually, before thickening the silicon single crystal from the seed crystal to a desired crystal diameter, an operation called necking for once narrowing down the diameter of the crystal grown from the seed crystal is performed.

Here, there is an upper limit to the thickness of necking for realizing dislocation-free, that is, the thickness of the dashes neck portion, and the single crystal is pulled up with the diameter of the dashes neck portion having this upper limit thickness. Has a problem in terms of tensile strength.

That is, when pulling a silicon single crystal having a large crystal diameter and a large weight, a dash neck portion (hereinafter, appropriately referred to as a neck portion) having a small diameter and insufficient mechanical strength is damaged. As a result, the intended purpose of pulling and growing the single crystal may not be achieved.

Therefore, in order to avoid such a situation,
As shown in FIG. 12, a hump-shaped portion is formed below the neck portion 7 of the single crystal 6, and a constricted engaged portion 8 having a sufficient mechanical strength is formed. The portion 8 is engaged with an engaging claw 17a of an engaging member 17 provided at the distal end of two wires 15R and 15L provided offset with respect to the crystal center axis 6c so as not to interfere with the main wire 10. While pulling up the two wires 15R and 15L, a method has been proposed. 17E is a hole provided in the engaging member 17E for allowing the main wire 10 to pass therethrough.

In this case, first, two wires 15R,
15L is wound up in the J1 direction by the wire winding section 20 of the gantry 3, and the engaging member 17 is on standby at a location away from the surface 5a of the melt 5 in the furnace body 2. And
When the main wire 10 is unwound by the wire winding unit 13, the seed crystal 12 hung by the main wire 10 via the seed chuck 11 is brought into contact with the melt 5, and then the main wire 10 is hoisted. Thus, the neck 7 is formed. Then, when the engaged portion 8 is formed, the engaging claw 17a of the engaging member 17 suspended by the two wires 15R and 15L is engaged with the engaged portion 8 of the single crystal 6. Then, the two wires 15R and 15L are wound down in the J2 direction. Thus, the engaging pawl 17 of the engaging member 17
After the single crystal 6 is engaged by a, the two wires 15R and 15L are raised in the J1 direction together with the main wire 10 while holding the single crystal 6 by the engaging member 17,
The single crystal 6 is pulled up.

As described above, in the prior art, since the main wire 10 from which the seed chuck 11 is suspended is arranged coaxially with the crystal center axis 6c, the wire from which the engaging member 17 is suspended is required. In order to avoid interference with the main wire 10, it is necessary to provide two or more wires (wires 15R and 15L) offset from the crystal center axis 6c.

However, these two wires 15R, 1R
When the single crystal 6 having a large weight is pulled up in the section from the position where the engaged portion 8 is formed to the single crystal growth end position using 5L, the winding of the wire is delicately controlled. The problem of having to do so. Furthermore, in pulling, it is necessary to perform so-called centering control for correcting the inclination of the engaging member 17 so that the central axis of the single crystal 6 coincides with the vertical axis.

That is, in the section from the position where the engaged portion 8 is formed to the end position of the single crystal growth, since the single crystal 6 to be pulled is heavy, the two wires 15R and 15L are connected. They may be elongated, and the amount of extension may be different between the left and right wires.

Therefore, the winding amount of the two wires must be corrected in a well-balanced manner, and delicate winding control must be performed so that the engaging member 17 can be lifted without tilting. Furthermore, in order to perform the above-mentioned centering control, it was necessary to provide a centering mechanism separately.

However, the accuracy of the winding control is increased,
Providing a separate centering mechanism leads to high costs.

Therefore, a pull-up device that does not require a delicate winding control for correcting such wire elongation in a well-balanced manner and does not require an additional alignment mechanism is proposed as shown in FIG.

The same reference numerals as those shown in FIG.

In the apparatus of FIG. 13, wires 15R, 15L
Instead of a rigid elevating member 1 which has no problem of elongation
5 'is used.

The upper end of the rigid elevating member 15 'is fixed to the gantry 3.
Is raised or lowered by the rod 20a of the raising / lowering actuator 20, through which the engaging member 17 is raised or lowered.

That is, in the apparatus shown in FIG. 13, the rod of the lifting actuator 20 is moved to move the engaging member 17 over a long section from the position where the engaged portion 8 is formed to the position where the single crystal growth is completed. It is necessary to extend the base 20a to a very high position by extending the base 20a very greatly.

For this reason, the lifting device itself becomes large, and a high building is required so that the gantry 3 does not reach the ceiling.

Further, in order to relatively move the gantry 3 with respect to the furnace body 2, it is necessary to provide a telescopic bellows 19 'between the furnace body 2 and the gantry 3 which is capable of shutting off the outside air.
The bellows 19 ′ must be very long and larger than the outer diameter of the single crystal 6 at the end of growth (the outer diameter of the straight body portion 9) in order to raise the entire gantry 3 very high.

However, the cost of the bellows itself is originally high, and if the bellows 19 'is long and has a large outer diameter, the cost is further increased.

As described above, even if the lifting device shown in FIG. 13 is adopted, a high building is required, and a long and large bellows 19 'having a large outer diameter is required. There is a problem that the size of the building becomes large and the building becomes large.

The present invention has been made in view of the above circumstances, and eliminates the need for a delicate winding control for correcting the elongation of the wire in a well-balanced manner and the need for an additional centering mechanism, and allows a high building to be constructed. An object of the present invention is to eliminate the need for a long bellows having a large outer diameter without using a bellows, thereby reducing the cost and making the apparatus compact and the building compact.

[0024]

Therefore, according to a first aspect of the present invention, there is provided a method for growing a single crystal by bringing a seed crystal into contact with a melt and pulling up the seed crystal from the melt. In the single crystal pulling apparatus, the seed crystal gripping member for gripping the seed crystal is suspended by a first elevating means for elevating and lowering by a single cord-like body, and is engaged with the engaged portion of the single crystal. A second elevating means for raising and lowering the engagement member which can be engaged by winding up or down the one cord-like body is provided.

That is, according to the first invention, FIGS.
As shown in (1), the seed crystal holding member 11 for holding the seed crystal 12 is
Is lowered to the melt contact position where it contacts the melt 5.

Then, as shown in FIGS. 3 and 8, the engaged portion 8 is formed on the single crystal 6 at least from the melt contact position by the first elevating means 13 as shown in FIGS. It is raised only during the stroke up to the engaged portion formation position.

Here, as shown in FIGS. 4 and 9, an engaging member 17 that can be suspended by the single rope 15 by the second lifting / lowering means 20 and can be engaged with the engaged portion 8. But,
It is lowered so as to engage with the engaged portion 8 to the engaged portion forming position.

Then, as shown in FIG. 5 and FIG.
The lifting means 20 of the above, during the stroke from the engaged portion forming position to the pulling end position of the single crystal 6,
By winding up a single cord 15, the engagement member 15
Is raised.

As described above, in the first invention, one cord 1
5, the section from the engaged portion forming position where the weight of the single crystal 6 becomes large to the pulling end position of the single crystal 6 is
Since the lifting is performed, unlike the conventional case, the situation where the elongation of the two wires varies is not caused, and the delicate winding control for correcting the elongation of the two wires in a well-balanced manner is not required. At the same time, it is not necessary to add an alignment mechanism.

Further, as described above, the long section from the engaged portion forming position to the pulling end position of the single crystal 6 is defined as the second section.
The single crystal 6 is pulled up by hoisting one cable 15 from a fixed position (fixed to the gantry 3) by the lifting / lowering means 20 (winding unit). 3 is raised very high to obtain a single crystal 6
The lifting device itself does not need to be high, as in the case of lifting, and a tall building is not required. In addition, a long bellows having a large outer diameter is not required.

In particular, as shown in FIG. 1, when the first lifting / lowering means 13 is constituted by a winding section, one rope 15
Wires 10R, 10L offset with respect to
The section where the single crystal 6 is pulled up only by the wires 10R and 10L is the section up to the engaged portion formation position (FIG. 3). Crystal 6 is still lightweight,
Elongation of the two wires 10R and 10L is unlikely to vary. Therefore, it is not necessary to delicately control the winding of the first lifting / lowering means 13, and it is not necessary to add an alignment mechanism.

In particular, as shown in FIG. 6, when the first lifting / lowering means 13 is constituted by a linear motion actuator, the seed crystal 12 is pulled up by the lifting / lowering member 10 '. The section in which the single crystal 6 is pulled up only by the member 10 'is a section up to the engaged portion forming position (FIG. 8). This section is short, and the rod 13a of the linear motion actuator 13 required to move this section. The stroke is short.

Therefore, although the entire gantry 3 rises, as in the prior art (FIG. 13), the more the gantry 3 is raised until the growth of the single crystal 6 is completed, the higher the pulling device itself becomes. That is not necessary, so a tall building is not required. And the bellows 19 can be shortened,
As a result, it is not necessary to extend the bellows 19 downward to the straight body portion 9 (FIG. 10), so that it is not necessary to make the outer diameter larger than that of the straight body portion 9, and the bellows can be made compact.

As described above, according to the first aspect of the invention, there is no need to add a delicate winding control for correcting the elongation of the wire in a well-balanced manner, or to add an aligning mechanism. Since a bellows having a large outer diameter is not required, the cost can be reduced, the apparatus can be made compact, and the building can be made compact.

Further, in the second invention, in the first invention,
As shown in FIGS. 1 and 6, one cord 15 is made of a single crystal 6
Are arranged coaxially with the central axis 6c.

That is, according to the second invention, the single crystal 6 is pulled up while the center of gravity of the single crystal 6 is positioned on the axis of the single cord-like body 15, so that the centering mechanism is not required, The centering control can be performed accurately.

In the third invention, in the first invention and the second invention, the engaging member has a play insertion portion into which the seed crystal holding member can be loosely inserted.
It is suspended by at least two cords offset with respect to the one cord.

According to the third aspect, as shown in FIGS. 1 and 6, the engaging member 17 has the loose insertion portion 17Q into which the seed crystal holding member 11 (21) can be loosely inserted. The crystal gripping member 11 (21) has a single cord 15 (crystal central axis 6).
It is suspended by at least two cords 10R, 10L (10'R, 10'L) offset with respect to c). Therefore, even if the seed crystal gripping member 11 and the engaging member 17 are at the same height when ascending and descending, they can be prevented from interfering with each other, and the single cord-like body 15 suspending them can be prevented. And at least two of the cords 10R and 10L can be prevented from interfering with each other.

Further, in the fourth invention, in the first invention,
In the first elevating means, the seed crystal holding member is suspended by a cord.

According to the fourth invention, as shown in FIG. 1, the seed crystal 12 is pulled up by, for example, two ropes 10R and 10L which are offset with respect to one rope 15. A single crystal 6 consists of only these two cords 10R and 10L.
Is a section up to the engaged portion forming position (FIG. 3).
Is still lightweight, and the elongation of the two cords 10R, 10L is unlikely to vary. Therefore, the first lifting / lowering means 1
Regarding 3, it is not necessary to perform the winding control delicately, and it is not necessary to add an alignment mechanism.

Further, in the fifth invention, the seed crystal holding member is suspended via an elevating member that supports the seed crystal holding member in a separable manner.

According to a sixth aspect, in the fifth aspect,
The first elevating means lowers the elevating member until the seed crystal reaches the melt contact position in a state where the seed crystal gripping member is hung, and moves the elevating member from the melt contact position to the cover. The second elevating means lowers the engaging member to the engaged portion forming position, and the second elevating means lowers the engaging member to the engaged portion forming position.
In the section from the engaged portion forming position to the single crystal pulling end position, the engaging member is raised together with the seed crystal gripping member separated from the elevating member.

According to the fifth and sixth aspects of the present invention, as shown in FIG. 6, the seed crystal holding member 11 (21) is suspended via a vertically movable lifting / lowering member 10 '.
In the section from the engaged portion forming position (FIG. 9) to the pulling end position of the single crystal 6 (FIG. 10), the second lifting / lowering means 20 is used.
Then, the engaging member 17 is raised together with the seed crystal gripping member 11 (21) separated from the lifting member 10 ', so that the first lifting means 13 lifts the lifting member 10', Only the section up to the engagement portion forming position (FIG. 8) is sufficient.

When the first lifting / lowering means 13 is constituted by a linear motion actuator, the single crystal 6 is formed only by the lifting / lowering member 10 '.
Is a section up to the engaged portion forming position (FIG. 8), this section is short, and the stroke of the rod 13a of the linear motion actuator 13 required for moving this section is short.

Therefore, although the entire gantry 3 rises, as in the prior art (FIG. 13), the more the gantry 3 is raised until the growth of the single crystal 6 is completed, the higher the pulling device itself becomes. That is not necessary, so a tall building is not required. And the bellows 19 can be shortened,
As a result, it is not necessary to extend the bellows 19 downward to the straight body portion 9 (FIG. 10), so that it is not necessary to make the outer diameter larger than that of the straight body portion 9, and the bellows can be made compact.

Further, in the seventh invention, in the fifth invention and the sixth invention, the elevating member 10 'is a rigid body.

For this reason, the problem of elongation does not arise at the time of lifting, and delicate elevation control is not required, and addition of a centering mechanism is not required.

According to an eighth aspect of the present invention, in the method for pulling a single crystal used for growing a single crystal by bringing the seed crystal into contact with the melt and then pulling the seed crystal from the melt, A step of lowering a seed crystal gripping member for gripping a crystal to a melt contact position at which the seed crystal comes into contact with the melt; A step of raising the engagement member to a position where the engagement portion is formed, and moving the engagement member suspended by a single cord-like body and capable of being engaged with the engaged portion to the engaged portion formation position. A process of lowering the engagement member so as to be engaged with the engagement portion, and a process of raising the engagement member by winding up the one cord-like body from the engaged portion formation position to the pulling end position of the single crystal. To have There.

According to the eighth aspect of the invention, the same effects as those of the first aspect of the invention can be obtained.

Of the first to eighth inventions described above, the invention excluding the fifth, sixth and seventh inventions is a single crystal 6
Can be applied to a device and a method for preventing the single crystal 6 from falling when the wire is pulled up by the cords 10R and 10L.

[0051]

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a block diagram showing an embodiment of an apparatus and a method according to the present invention.

First Embodiment FIG. 1 shows the configuration of a single crystal pulling apparatus 1 (single crystal growth apparatus) of the present embodiment. FIG. 1B is an A view of FIG. 1A. In this embodiment, as a single crystal,
A silicon (Si) single crystal is assumed.

FIG. 1 shows a first embodiment in which a seed crystal is pulled up by winding up a cord-like body.

As shown in FIG. 1, the apparatus of this embodiment is
Broadly, it comprises a furnace body 2 and a gantry 3 provided on the furnace body 2.

A crucible 4 in which a silicon melt 5 is filled is provided in the furnace body 2. In the drawings, a heater for melting the silicon melt 5, a mechanism for rotating the crucible 4, and the like are omitted. The inside of the furnace body 2 is evacuated to about several tens of torr, and is filled with argon gas. Thus, the inside of the furnace body 2 is almost in a vacuum and is in a high temperature state.

A single crystal 6 is grown in the furnace body 2.
The central axis 6 c (crystal central axis) of the single crystal 6 coincides with the central axis of the furnace body 2 or the central axis of the gantry 3.

The single crystal 6 is pulled up and grown by the two wires 10R and 10L as cords. It should be noted that another cord, for example, a chain may be used instead of the wires 10R and 10L.

That is, a bar-shaped seed chuck suspension member 21 is suspended from the lower ends of the two wires 10R and 10L, and the seed crystal 12 is fixed via the wire or the rigid member 10. The seed chuck 11 to be held is suspended. The single crystal 6 is grown by pulling up the seed crystal 12.

In the gantry 3, the two wires 10R,
A wire winding unit 13 for winding 10L is provided.
By the wire winding section 13, the two wires 10R, 1
0L is wound up and down,
Seed chuck 11 and seed chuck hanging member 2
1 is raised in the J1 direction and lowered in the J2 direction.

A wire take-up section 20 for winding one wire 15 as one cord-like body is provided in the gantry 3. Instead of this one wire 15, another cord, for example, a chain may be used.

The single wire 15 is connected to the crystal center axis 6c.
It is arranged so that it may become coaxial with. The two wires 10R and 10L described above are arranged offset from one wire 15 (crystal central axis 6c).

At the lower end of the one wire 15, an engaging member 17 that engages with the engaged portion 8 formed on the single crystal 6 is suspended. Therefore, the wire winding section 20
As a result, one wire 15 is wound up and down, whereby the engaging member 17 is raised in the J1 direction and lowered in the J2 direction.

The engaging member 17 has a U-shaped frame 17.
F and a pair of engaging claws 17a, 17a arranged in an opening at the lower end of the frame 17F. The engagement claw 17a is rotatable only in the direction E, which is an upward direction (counterclockwise) from the initial rotation position, with the shaft 17b as a rotation axis, and is provided with a rotation stopper for restricting rotation in the downward direction. ing. And, this engaging claw 17a is
As shown in (b), when the engaging member 17 descends,
While rotating in the E direction along the surface of the single crystal 6, the lower F
, And can be returned to the initial rotation position when it is located at the engaged portion 8.

Therefore, when the single crystal 6 is pulled up in a state where the engaging claw 17a is located at the engaged portion 8 of the single crystal 6, the engaging claw 17a is fixed at the initial rotation position by the rotation stopper. Thus, the engagement with the engaged portion 8 is ensured.

The engaging member 17 is connected to the seed chuck 11.
The seed chuck hanging member 21 has a play insertion portion 17Q into which 1) can be loosely inserted. Then, as shown in an arrow A view of FIG. 1A of FIG.
R and 10L are offset from one wire 15 so as to sandwich the frame 17F of the engaging member 17.

Therefore, even if the seed chuck 11, the seed chuck suspending member 21 and the engaging member 17 are at the same height when ascending and descending, it is possible to prevent interference between them, Can also be prevented from interfering with one wire 15 suspending the two wires 10R and 10L.

The seed chuck 11 and the seed chuck suspending member 21 may be integrally formed. That is, the integral seed crystal holding member is connected to two wires 10R,
It may be raised and lowered by 10 L.

In FIG. 1, two wires 10R, 1R
Although the seed chuck hanging member 21 is moved up and down by 0L, three or more wires may be used.

Further, in FIG. 1, the engaging member 17 is constituted by a U-shaped frame 17F. However, in order to increase the strength, it is also possible to carry out reinforcement by providing a strut bar or the like as appropriate. is there.

The shape of the engaging member 17 is arbitrary, and an embodiment using an engaging member 17 'as shown in the perspective view of FIG. 11 is also possible.

An engaging member 17 ′ shown in FIG. 11 has a U-shaped frame 17 C suspended on a single wire 15.
And a circular frame 17D connected to the lower end of the U-shaped frame 17C. The engaged portion 8 of the single crystal 6 is engaged with the inner peripheral surface of the circular frame 17D. A pair of engaging claws 17a, 17a are provided.

The diameter of the opening of the circular frame 17D (the distance between the pair of engaging claws 17a, 17a) is set so that the seed chuck hanging member 21 can be inserted through the opening. 21 is longer than the length in the longitudinal direction.

In FIG. 1, the gantry 3 is turned around the crystal center axis 6c (turning direction B) by a turning mechanism (not shown).

Therefore, when the turning mechanism is operated, the engaging member 17 and the seed chuck 11 (the seed crystal 1) are moved.
2) is turned together with the gantry 3.

Next, a process for growing a single crystal 6 in the single crystal pulling apparatus 1 will be described.

First Step (See FIG. 2) First, the wires 10R, 10R
L is unwound, and the seed crystal 12 held by the seed chuck 11 at the end of the wire 10R, 10L is lowered in the J2 direction to a position where it comes into contact with the melt 5.

Next, the wires 10 R and 10 L are wound by the wire winding section 13, and the seed crystal 12 is raised from the surface 5 a of the melt 5 in the J 1 direction.

From the start of single crystal growth to the end of single crystal growth, the gantry 3 is rotated in the counterclockwise direction B around the crystal center axis 6c by a turning mechanism (not shown).

Therefore, the wires 10R and 10L, the wire 15, and the single crystal 6 suspended therefrom are rotated in the same direction B from the start of the single crystal growth to the end of the single crystal growth.

Thus, first, the neck portion 7 is formed.

Second Step (See FIG. 3) Next, by forming a hump-shaped portion below the neck portion 7, a constricted shape having a larger diameter and greater mechanical strength than the neck portion 7 is formed. Is formed.

The constricted portion 8 includes a minimum diameter portion 8b having a minimum diameter as a constricted portion, and a constricted upper portion 8a above the minimum diameter portion 8b. That is, the engaged portion 8 has an inverted conical shape in which the diameter gradually increases from the minimum diameter portion 8b.

Now, the wire take-up section 20 operates so that one wire 15 is completely wound up.
The engaging member 17 suspended from one wire 15 is retracted to an upper position away from the engaged portion 8 of the single crystal 6.

Third Step (See FIG. 4) Then, when the engaged portion 8 is formed on the single crystal 6, the wire winding section 20 is operated so as to wind down one wire 15. You. The engaging member 17 is provided with the engaging claw 1.
Arrow J until the position 7a engages with the engaged portion 8 of the single crystal 6.
It is lowered in two directions. At the time of this lowering, the seed chuck suspending member 21 and the like are loosely inserted into the loose insertion portion 17Q of the engaging member 17, so that these seed chuck suspending members 2
Interference between the first member and the engaging member 17 is prevented. Also, 2
Since the wires 10R and 10L are arranged offset with respect to the single wire 15 so as to sandwich the frame 17F of the engagement member 17, interference such as entanglement of these wires is also prevented. .

FIG. 4B shows the engagement pawl 17 of the engagement member 17.
FIG. 6A is a diagram showing a state in which a is engaged with an engaged portion 8 of a single crystal 6.

[0086] As shown in FIG.
Is moved downward along the surface of the single crystal 6 while rotating in the E direction. When the engagement claw 17a is located at the minimum diameter portion 8b of the engaged portion 8, the engagement claw 17a returns to the initial rotation position.

Fourth stroke (see FIG. 5) When the engaging claw 17a of the engaging member 17 is positioned at the engaged portion 8 of the single crystal 6, the wire winding portion 20
It is operated to wind up the book wire 15.

At this time, one wire 15 is lifted in synchronization with the winding operation of the two wires 10R and 10L by the wire winding unit 13. For this reason, the engagement member 17
Is raised in the direction of arrow J1 in synchronization with the seed chuck 11.

With the engagement claws 17a thus positioned at the minimum diameter portion 8b of the engaged portion 8 of the single crystal 6, the engagement member 1
7, the engaging claw 17a eventually becomes the minimum diameter portion 8b.
At the constricted upper portion 8a, which is higher than the upper portion, it is fixed at the initial rotation position by the rotation stopper. That is, the engagement claw 1
7 a is securely engaged with the engaged portion 8.

Therefore, the engagement claws 17a of the engagement member 17
The single crystal 6 can be pulled up in a state where the single crystal 6 is securely engaged with the engaged portion 8.

As described above, the engaging member 17 is engaged with the constricted engaged portion 8 having high mechanical strength, and the single crystal 6 is pulled up, so that the neck portion 7 of the single crystal 6 is damaged. The single crystal 6 can be grown without performing this.

After the formation of the above-mentioned constricted portion 8 to be engaged, shouldering is performed, and a straight body portion 9 is formed. Eventually, the tail portion is squeezed, and the pulling process of the single crystal 6 ends (the single crystal growth ends).

As described above, according to the first embodiment,
With one wire 15, the pulling end position of the single crystal 6 from the engaged portion forming position (see FIG. 4) where the weight of the single crystal 6 becomes large (see FIG. 4). The section up to the time of forming the torso is shown).
A situation in which the elongation of the two wires varies does not occur, so that delicate winding control for correcting the elongation of the two wires in a well-balanced manner becomes unnecessary, and the addition of a centering mechanism becomes unnecessary.

In particular, in the first embodiment, one wire 15 is arranged coaxially with the central axis 6 c of the single crystal 6, and the center of gravity of the single crystal 6 is located on the axis of one wire 15. Since the single crystal 6 is pulled up while being positioned, accurate centering control can be performed without the need for a centering mechanism.

In addition, as described above, one wire 15 is wound up from the fixed position of the gantry 3 in the long section from the engaged portion forming position to the pulling up end position of the single crystal 6 by the wire winding section 20. Since the single crystal 6 is pulled up, the pulling device 1 itself is raised as in the case where the entire base 3 is raised very high as in the prior art shown in FIG. Nothing,
Elevated buildings are not required. In addition, a long bellows having a large outer diameter is not required.

However, the seed chuck 11 (seed crystal 1
Regarding 2), the section where the single crystal 6 is pulled up by only the two wires 10R and 10L is pulled up to the engaged portion formation position (FIG. 3). In this section, the single crystal 6 to be pulled is still lightweight, and has two wires 10R, 10R.
There is little variation in the elongation of L. Therefore, it is not necessary to delicately control the winding of the wire winding section 13, and it is not necessary to add an alignment mechanism.

As described above, according to the first embodiment, there is no need for a delicate winding control for compensating for the elongation of the wire in a well-balanced manner, and it is not necessary to add a centering mechanism. In addition, since a long bellows having a large outer diameter is not required, the cost can be reduced, the apparatus can be made compact, and the building can be made compact.

Second Embodiment In the first embodiment described above, the cords 10R, 1R,
Although the seed crystal 12 is pulled up by winding up 0 L, the seed crystal 12 may be pulled up in accordance with expansion and contraction of the linear motion actuator.

FIG. 6 is a diagram for explaining a second embodiment in which a linear motion actuator 13 is used as an actuator for pulling up the seed crystal 12.

The components having the same reference numerals as those of the single crystal pulling apparatus 1 shown in FIG. 1 have the same functions and will not be described.

As shown in FIG. 6, the apparatus according to the second embodiment mainly includes a furnace body 2 and a gantry 3 whose vertical position can be changed relative to the furnace body 2. I have.

The gantry 3 is connected to the furnace body 2 via a telescopic bellows 19. The bellows 19 is provided to block the inside of the furnace body 2 from outside air.

The gantry 3 is connected to the furnace body 2 via the magnetic seal 18.
Are disposed so as to be movable up and down (J1 and J2 directions) and to be pivotable about the crystal center axis 6c (rotation direction B).

The elevating actuator 13 as a linear actuator is an actuator for raising the seed chuck 11 and the seed crystal 12 fixedly held by the same together with the gantry 3 in the J1 direction and lowering the seed crystal 12 in the J2 direction. .

That is, the tip of the rod 13 a of the lifting actuator 13 is connected to the table 22. The gantry 3 is turned around the crystal center axis 6c (turning direction B) with respect to the table 22 by a turning mechanism (not shown).

A rigid lifting member 10 ′ is suspended from the fixed position of the gantry 3. A seed chuck suspending member 21 is supported by the elevating member 10 ′ so as to be separable upward, and the seed crystal 12 is fixedly held on the seed chuck suspending member 21 via a rigid member 10T. Seed chuck 11 is suspended. Therefore, when the turning mechanism for turning the gantry 3 is operated, the seed chuck 11 (the seed crystal 1) is turned on.
2) is turned in the B direction together with the gantry 3 (the engaging member 17 is also turned).

As the rod 13a of the elevating actuator 13 is extended and retracted, the seed chuck 11 (seed crystal 12) is raised in the J1 direction and lowered in the J2 direction.

Next, a process for growing a single crystal 6 in the single crystal pulling apparatus 1 will be described.

First Step (See FIG. 7) First, the rod 13a of the lifting actuator 13 is retracted, whereby the lifting member 10 'is lowered, and accordingly, the seed chuck 11 at the lower end of the lifting member 10' is moved downward. J2 until the held seed crystal 12 contacts the melt 5
Descended in the direction.

Next, the elevating member 10 ′ is raised by extending the rod 13 a of the elevating actuator 13, whereby the seed crystal 12 is deposited on the surface 5 of the melt 5.
It is raised in the J1 direction from a.

From the start of single crystal growth to the end of single crystal growth, the gantry 3 is rotated counterclockwise B around the crystal center axis 6c by a turning mechanism (not shown).

Therefore, the elevating member 10 ', the single wire 15, and the single crystal 6 suspended therefrom are rotated in the same direction B from the start of the single crystal growth to the end of the single crystal growth.

Thus, first, the neck portion 7 is formed.

Second Step (See FIG. 8) Next, by forming a hump-shaped portion under the neck portion 7, a constricted shape having a larger diameter and greater mechanical strength than the neck portion 7 is formed. Is formed.

The constricted engaged portion 8 includes a minimum diameter portion 8b having a minimum diameter among the constriction portions, and a constriction upper portion 8a above the minimum diameter portion 8b. That is, the engaged portion 8 has an inverted conical shape in which the diameter gradually increases from the minimum diameter portion 8b.

Now, the wire take-up section 20 operates so that one wire 15 is completely wound up.
The engaging member 17 suspended from one wire 15 is retracted to an upper position away from the engaged portion 8 of the single crystal 6.

Third Step (See FIG. 9) When the engaged portion 8 is formed on the single crystal 6, the wire winding section 20 is operated so as to wind down one wire 15. You. The engaging member 17 is provided with the engaging claw 1.
Arrow J until the position 7a engages with the engaged portion 8 of the single crystal 6.
It is lowered in two directions. At the time of this lowering, the seed chuck suspending member 21 and the like are loosely inserted into the loose insertion portion 17Q of the engaging member 17, so that these seed chuck suspending members 2
Interference between the first member and the engaging member 17 is prevented. Also, two linear members 10'R, 1 constituting the lifting member 10 '
0′L is offset with respect to one wire 15 so as to sandwich the frame 17F of the engaging member 17, so that these wires 15 and the two linear members 1
Interference with 0'R and 10'L is also prevented.

The engaging claw 17a of the engaging member 17 is engaged with the engaged portion 8 of the single crystal 6, as shown in FIG. 4B, as in the first embodiment.

Fourth stroke (see FIG. 10) When the engaging claw 17a of the engaging member 17 is positioned at the engaged portion 8 of the single crystal 6, the wire winding portion 20
It is operated to wind up the book wire 15.

Therefore, the engagement member 17 is raised in the direction of arrow J1.

With the engagement pawl 17a positioned at the minimum diameter portion 8b of the engaged portion 8 of the single crystal 6, the engagement member 1
7, the engaging claw 17a eventually becomes the minimum diameter portion 8b.
At the constricted upper portion 8a, which is higher than the upper portion, it is fixed at the initial rotation position by the rotation stopper. That is, the engagement claw 1
7 a is securely engaged with the engaged portion 8.

Therefore, the engagement claws 17a of the engagement member 17
The single crystal 6 can be pulled in a state where the single crystal 6 is securely engaged with the engaged portion 8.

In the second embodiment, unlike the first embodiment, thereafter, only one wire 15 is lifted,
Single crystal 6 is pulled up.

That is, the seed chuck suspension member 21
Is suspended by the elevating member 10 ′ so as to be separable upward, so that the seed chuck suspending member 21 is separated upward from the elevating member 10 ′ as the engaging member 17 rises, Reference numeral 17 denotes the separated seed chuck hanging member 21 (seed chuck 11, seed crystal 1).
It is raised with 2).

In this way, the engagement member 17 is engaged with the constricted portion 8 having a large mechanical strength while the single crystal 6 is engaged.
Is pulled up, so that single crystal 6 can be grown without causing breakage at neck 7 of single crystal 6.

After the formation of the above-mentioned constricted portion 8 to be engaged, shouldering is performed to form the straight body portion 9. Eventually, the tail portion is squeezed, and the pulling process of the single crystal 6 ends (the single crystal growth ends).

As described above, according to the second embodiment,
As in the first embodiment, by one wire 15,
The position where the engaged portion is formed where the weight of the single crystal 6 becomes large (FIG. 9
(See FIG. 10).
Since the section up to this point is raised, a situation in which the elongation of the two wires varies as in the prior art shown in FIG. Delicate winding control becomes unnecessary, and the addition of an aligning mechanism becomes unnecessary.

In particular, in the second embodiment, one wire 15 is arranged coaxially with the central axis 6c of the single crystal 6, and the center of gravity of the single crystal 6 is on the axis of one wire 15. Since the single crystal 6 is pulled up while being positioned, accurate centering control can be performed without the need for a centering mechanism.

Further, as described above, the single wire 15 is wound up from the fixed position of the gantry 3 by the wire winding section 20 in the long section from the engaged portion forming position to the pulling end position of the single crystal 6. Since the single crystal 6 is pulled up, the pulling device 1 itself is raised as in the case where the entire base 3 is raised very high as in the prior art shown in FIG. Nothing,
Elevated buildings are not required. In addition, a long bellows having a large outer diameter is not required.

In the second embodiment, the seed chuck suspending member 21 is suspended via an elevating member 10 ′ which is supported in an upwardly separable manner. In the section up to the pulling end position of the single crystal 6 (FIG. 10), one wire 15 is wound up, and the engaging member 17 is raised together with the seed chuck hanging member 21 separated from the elevating member 10 ′. Therefore, the section in which the linear actuator 13 is operated and the elevating member 10 'is pulled up may be only the section up to the engaged portion formation position (FIG. 8).

In other words, the section in which the elevating member 10 'is raised to pull up the single crystal 6 is the section up to the engaged portion formation position (FIG. 8), and this section is short. The rod 13 of the required linear motion actuator 13
The stroke of a may be short.

Therefore, in this section, although the entire gantry 3 rises, as the whole gantry 3 is raised until the growth of the single crystal 6 is completed as in the prior art (FIG. 13), the pulling device itself is increased. The building does not need to be high, and a tall building is not required. The bellows 19 can also be shortened, and as a result, there is no need to extend the bellows 19 downward to the straight body portion 9 (FIG. 10).
It is not necessary to make the outer diameter larger than this, and the bellows can be made compact.

In particular, when the elevating member 10 ′ is made of a rigid body, the problem of elongation does not occur when the elevating member 10 ′ is pulled up, so that delicate elevating control is not required, and an additional centering mechanism is not required. Is obtained. The elevating member 10 'may be other than a rigid body.

As described above, according to the second embodiment, there is no need for a delicate winding control for correcting the wire elongation in a well-balanced manner, and it is not necessary to add a centering mechanism. In addition, since a long bellows having a large outer diameter is not required, the cost can be reduced, the apparatus can be made compact, and the building can be made compact.

In the first embodiment, the seed crystal 12 is pulled up by the two wires 10R and 10L. However, the seed crystal 12 is pulled up by the single wire 10 via a moving pulley. Is also good.

FIG. 14 shows one wire 10 (cord 1).
0) illustrates a third embodiment in which the seed crystal 12 is pulled up. The same components as those in the first embodiment are denoted by the same reference numerals, and description thereof will be omitted.

As shown in FIG. 14, the bearing 31 to which the seed chuck 11 for holding the seed crystal 12 is fixed is fixed.
In FIG. 14, a movable pulley 30 is rotatably supported about a shaft 31a as a rotation axis (see FIG.
(C)). One wire 10 is suspended from the moving pulley 30, and one end of the wire 10 is connected to the wire winding section 1.
3, so that it can be wound up. The other end of the wire 10 is fixed to a predetermined position of the gantry 3.

Here, as shown in FIG. 14 (b), which shows a view A in FIG. 14 (a), both ends 10-1 and 10-2 of the wire 10 on which the moving pulley 30 is suspended It is offset from one wire 15 so as to sandwich the 17 frames 17F.

As described above, the wire 10 is wound up and down by the wire winding section 13, so that the seed crystal 12 fixed and held on the seed chuck 11 is held.
Is raised or lowered.

In this case, since the wire 10 is moved up and down by using the movable pulley 30, a rising stroke (a descending stroke) of the wire 10 by the wire winding section 13 is increased.
In addition, the ascent stroke (descending stroke) of the seed crystal 12 is halved (the resolution is doubled). As a result, the precision of the pulling control of the single crystal 6, specifically, the precision of the winding control of the wire winding unit 13 is improved as compared with the apparatus of the first embodiment.

Further, as in the first embodiment, one wire 10 is wound without winding each of the two wires 10R and 10L. There is no variation in elongation, and the control accuracy is further improved.

In order to minimize the influence of the dust generated by the rotation of the moving pulley 30 on the quality of the single crystal 6, the moving pulley 3
0 may be entirely covered with the cover 32.

In the first and third embodiments, the single crystal 6 is positively engaged with the engaging member 17 suspended from the single wire 15 so that the two wires 10R ,
Although it is assumed that one wire 15 is mainly pulled up rather than 10L (or one wire 10), the present invention mainly uses two wires 10R and 10L (or one wire 10) as a single crystal 6 When raising
One wire 15 may be used to prevent the single crystal 6 from dropping.

That is, in the first embodiment, the single crystal 6 is composed of two wires 10R and 10L.
And these two wires 10R,
It is raised by winding up 10L. During this pulling, for example, even if the neck 7 of the single crystal 6 is broken, the engaging claw 17a of the engaging member 17 is located at a position where the engaged portion 8 below the neck 7 can be engaged. Is positioned, the portion below the neck portion 7 does not fall, and the engaging claw 17a of the engaging member 17 is securely engaged with the engaged portion 8 of the single crystal 6. It is possible to continue raising the vehicle while keeping it.

[Brief description of the drawings]

FIG. 1 is a diagram showing a configuration of a single crystal pulling apparatus according to a first embodiment of the present invention.

FIG. 2 is a diagram showing a first step of the first embodiment.

FIG. 3 is a diagram showing a second step of the first embodiment.

FIG. 4 is a diagram showing a third step of the first embodiment.

FIG. 5 is a diagram showing a fourth step of the first embodiment.

FIG. 6 is a diagram showing a configuration of a single crystal pulling apparatus according to a second embodiment of the present invention.

FIG. 7 is a diagram showing a first step of the second embodiment.

FIG. 8 is a diagram showing a second step of the second embodiment.

FIG. 9 is a diagram showing a third step of the second embodiment.

FIG. 10 is a diagram showing a fourth step of the second embodiment.

FIG. 11 is a perspective view showing a modification of the engagement member.

FIG. 12 is a diagram showing a configuration of a conventional single crystal pulling apparatus.

FIG. 13 is a diagram showing a configuration of a conventional single crystal pulling apparatus different from FIG.

FIG. 14 is a diagram showing a configuration of a single crystal pulling apparatus according to a third embodiment of the present invention.

[Explanation of symbols]

 Reference Signs List 5 melt 5a melt surface 6 single crystal 6c crystal center axis 8 engaged portion 10R, 10L wire 10 'elevating member 11 seed chuck 12 seed crystal 13 wire winding portion 15 one wire (one cord) 17) Engagement member 17a Engagement claw 20 Lifting actuator (wire winding section) 21 Seed chuck suspension member

Claims (13)

[Claims] 1. A single crystal pulling apparatus used for growing a single crystal by bringing a seed crystal into contact with a melt and then pulling the seed crystal from the melt, wherein the seed holding the seed crystal is provided. A first elevating means for elevating and lowering the crystal gripping member; and an engaging member suspended by one cord and capable of engaging with the engaged portion of the single crystal, the one cord. And a second elevating means for raising and lowering by winding up or down. 2. The single crystal pulling apparatus according to claim 1, wherein the one cord-like body is disposed coaxially with a central axis of the single crystal. 3. The engaging member has a loose insertion portion into which the seed crystal gripping member can be loosely inserted, and the seed crystal gripping member is offset with respect to the one cord-like body. 3. The single crystal pulling apparatus according to claim 1, wherein the single crystal is suspended by at least two cords. 4. The first elevating means, wherein the seed crystal gripping member is suspended by a cord.
An apparatus for pulling a single crystal as described above. 5. The single crystal pulling apparatus according to claim 1, wherein the seed crystal holding member is suspended via an elevating member that supports the seed crystal holding member in a separable manner. 6. The first lifting unit moves the lifting member in a state where the seed crystal holding member is suspended.
The seed crystal is lowered until it reaches a melt contact position where it comes into contact with the melt, and is raised from this melt contact position until it reaches an engaged portion forming position where an engaged portion is formed on the single crystal. Wherein the second elevating means lowers the engaging member to the engaged portion forming position, and in a section from the engaged portion forming position to the pulling end position of the single crystal,
The single crystal pulling apparatus according to claim 5, wherein the engaging member is raised together with the seed crystal holding member separated from the elevating member. 7. The elevating member is a rigid body.
Or the single crystal pulling apparatus according to claim 6. 8. A method for pulling a single crystal used for growing a single crystal by bringing a seed crystal into contact with a melt and then pulling the seed crystal from the melt, wherein the seed holding the seed crystal is provided. Lowering the crystal gripping member to a melt contact position at which the seed crystal comes into contact with the melt; and engaging the seed crystal gripping member at an engaged portion forming position where the engaged portion is formed on the single crystal. And engaging the engaging member, which is suspended by one cord-like body and can be engaged with the engaged portion, to the engaged portion to the engaged portion formation position. A single crystal having a step of lowering the engaging member and a step of raising the engaging member by rolling up the one cord-like body from the engaged portion forming position to the pulling end position of the single crystal. How to raise. 9. A single crystal drop prevention device for preventing a single crystal from falling when a single crystal is grown by bringing the seed crystal into contact with the melt and then pulling up the seed crystal from the melt. A first elevating means for elevating and lowering a seed crystal gripping member for gripping the seed crystal, and an engaging member suspended by one cord-like body and capable of being engaged with the engaged portion of the single crystal, A single crystal falling prevention device comprising: a second elevating means for raising and lowering the one wire-like body by winding up or down. 10. The single crystal drop prevention device according to claim 9, wherein said one cord-like body is arranged coaxially with a central axis of said single crystal. 11. The engaging member has a play insertion portion into which the seed crystal holding member can be loosely inserted, and the seed crystal holding member is offset with respect to the one cord-like body. The single crystal falling prevention device according to claim 9 or 10, wherein the device is suspended by at least two cords. 12. The single crystal falling prevention device according to claim 9, wherein the first elevating means is configured such that the seed crystal holding member is suspended by a cord. 13. A method for preventing a single crystal from falling when a single crystal is grown by bringing the seed crystal into contact with the melt and then pulling up the seed crystal from the melt. A step of lowering a seed crystal gripping member that grips the seed crystal to a melt contact position where the seed crystal comes into contact with the melt; and an engaged portion of the seed crystal gripping member is formed on the single crystal. And moving the engaging member suspended by a single cord-like body and capable of being engaged with the engaged portion to the engaged portion forming position. A step of lowering the engagement member so that it can be engaged with the engaged portion, and raising the engagement member by winding up the one cord-like body from the engaged portion forming position to the pulling end position of the single crystal. And said Child crystals gripping member, wherein one of the fall prevention method of a single crystal comprising the step of raising up pulling the end position of the single crystal while synchronizing the winding of the cord-like member.