JP2000211989A - Single crystal pulling apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a single crystal pulling apparatus capable of readily cleaning an isolation valve means, etc., not burdening an operator, having a small installation space for the pulling apparatus and contributing to improvement in productivity. SOLUTION: In this single crystal pulling apparatus equipped with an isolation valve means 4 for dividing a main chamber 2 for storing a heating means for heating a crucible from a subsidiary chamber 3 equipped with a pulling means for pulling up a single crystal, the valve means 4 has an isolation valve 11 for opening and closing a communicating hole 10 installed between both the chambers 2 and 3, a valve storage part 12 capable of horizontally moving the isolation valve 11, an opening part 13 capable of taking in and out the isolation valve 11 at one wall 12s of the valve storage part 12 and a lid body 14 which is detachably installed so as to close the opening part 13 and is pivotally attached through a rotation space reducing means 19 of the lid body 14 to the valve storage part 12 during opening of the opening part 13.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a pulling apparatus for pulling a semiconductor single crystal by the CZ method, and in particular, it is easy to clean an isolation valve and the like, the installation space for the pulling apparatus is small, and a single unit that contributes to improvement in productivity. The present invention relates to a crystal pulling apparatus.

[0002]

2. Description of the Related Art Conventionally, in a silicon single crystal pulling apparatus 31 for pulling a silicon single crystal Ig by a CZ method as shown in FIG. 7, a raw material polysilicon is heated and melted and stored as a melt S. Main chamber 34 containing heater 33 for heating crucible 32 and the like
And a sub-chamber 35 provided with a pulling means for pulling a single crystal Ig from the inside of the quartz crucible 32 by the seed crystal s, and an isolation valve means 3 between the two chambers 34, 35.
6 is provided to be able to advance and retreat. The isolation valve means 36 has a valve housing 37 and an isolation valve 38 provided in the valve housing 37 so as to be movable forward and backward.
In order to remove g, while the silicon single crystal Ig is lifted above the isolation valve 38, the isolation valve 38 housed in the valve housing 37 is advanced to close the communication port 39, and the main chamber 34 is closed. While maintaining the pressure in a reduced pressure state, the sub-chamber 35 is restored to normal pressure and the single crystal Ig is taken out. Thereafter, the pressure in the sub-chamber 35 is reduced, the isolation valve 38 is retracted to open the upper opening 39, and the single crystal Ig is pulled up again.

[0003]

When such pulling of the silicon single crystal is repeated, the silicon gas generated from the melt in the quartz crucible 32 is deposited on the inner wall of the single crystal pulling apparatus and on the isolation valve 38 and the like. To form a film. The peeling of the film causes the generation of dust, and the dust falls into the quartz crucible 32, and the silicon single crystal Ig is removed.
Causes dislocations in

Therefore, it is necessary to frequently clean the isolation valve 38 and the like. However, the isolation valve means 36 is in a state of being housed in the valve housing part 37 due to its structure.
Is difficult to expose outside the valve housing 37,
Therefore, cleaning of the isolation valve 38 was not easy.

Therefore, as shown in FIG. 8, a semiconductor single crystal pulling apparatus 42 having an isolation valve means 41 is used. The isolation valve means 41 is provided between a main chamber 43 containing a quartz crucible, a heater and the like and a sub-chamber 44 provided with a pulling means for pulling a single crystal. An isolation valve 46 that opens and closes an opening 45 communicating the chambers 43 and 44, a rotation mechanism 47 that horizontally rotates the isolation valve 46, and a valve that is formed so that the isolation valve 46 can be horizontally rotated. A housing 48, an opening 49 formed in one side wall of the valve housing 48 so that the isolation valve 46 can enter and exit, and a lid 50 having a planar shape which is detachably screwed so as to close the opening 49. have.

In the isolation valve means 41 having such a structure, the isolation valve 46
When cleaning the like, the screw 51 is removed, the opening 49 is opened, the rotating mechanism 47 is driven, and the isolation valve 46 is moved from the opening 49 to the valve housing 4.
8 and cleaning the isolation valve 46. Since the isolation valve 46 can be easily exposed outside the valve housing portion 48, cleaning of the isolation valve 46 is also easy.

However, in the semiconductor single crystal pulling apparatus 42 having such an isolation valve means 41, the radius of rotation of the isolation valve 46 is large, and when the radius of rotation of the isolation valve 46 is rotated, the isolation valve 46 is rotated. However, since this hits surrounding members such as pipes and columns, a large installation space for the single crystal pulling apparatus had to be taken.

Therefore, there has been a demand for a single crystal pulling apparatus which can easily clean the isolation valve means and the like, does not place a burden on an operator, has a small installation space for the pulling apparatus, and contributes to an improvement in productivity.

The present invention has been made in consideration of the above-mentioned circumstances, and it is easy to clean the isolation valve means, etc., so that no burden is imposed on the operator, the installation space of the pulling device is small, and the productivity is improved. It is an object to provide a single crystal pulling apparatus that contributes.

[0010]

Means for Solving the Problems To achieve the above object, the invention of claim 1 of the present application provides a main chamber containing a crucible for melting a semiconductor material and heating means for heating the crucible; A sub-chamber provided with pull-up means for pulling a single crystal from a crucible by a seed crystal; and a single crystal pulling apparatus provided with isolation valve means between the two chambers so as to partition both chambers. The isolation valve means includes an isolation valve for opening and closing a communication port provided between the two chambers, a valve storage portion in which the isolation valve is formed to be horizontally movable, and an isolation valve on one side wall of the valve storage portion. And an opening formed so as to be able to enter and exit, and detachably attached so as to close this opening, Hotoki, and summarized in that a single crystal pulling apparatus, characterized in that it comprises a lid which is pivotally mounted on the valve housing portion via a rotary space-reducing means of the lid.

In the invention of claim 2 of the present application, the rotation space reducing means comprises a hinge for pivotally connecting the lid to the valve housing, and the hinge is provided with a linear guide for holding the lid so as to be able to move forward and backward. The gist is a single crystal pulling apparatus according to claim 1.

According to a third aspect of the present invention, the isolation valve is horizontally rotated by a rotation support arm rotated by a drive motor.
Or the single crystal pulling apparatus according to item 2.

[0013] In the invention of claim 4 of the present application, the lid is formed with a storage recess for storing a part of the isolation valve when the isolation valve is on standby. The gist of the present invention is that the apparatus is a single crystal pulling apparatus according to item 1.

[0014]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of a single crystal pulling apparatus according to the present invention will be described below with reference to the accompanying drawings.

As shown in FIG. 2, the single crystal pulling apparatus 1 according to the present invention has a main chamber 2 and a sub-chamber 3, between which the two chambers 2, 3 are located.
Are provided as appropriate.

The main chamber 2 includes a crucible, eg, a quartz crucible 5 for melting the semiconductor material, a graphite crucible 6 in which the quartz crucible 5 is stored, a heating means 7 for heating the quartz crucible 5 through the graphite crucible 6, and graphite. A crucible rotating shaft 8 that rotates the crucible 6 and the quartz crucible 5 and penetrates the main chamber 2 is provided. The sub-chamber 3 has a pulling means 9 having a wire 9a for pulling a single crystal Ig by the seed crystal s, and has a space for accommodating the pulled single crystal Ig.

As shown in FIG. 1, the isolation valve means 4 provided between the chambers 2 and 3 includes an isolation valve 11 for opening and closing a communication port 10 provided between the chambers 2 and 3. A valve housing 12 in which the isolation valve 11 is formed to be horizontally movable.
And an opening 13 formed in one side wall 12s of the valve housing 12 so that the isolation valve 11 can enter and exit.
And a lid 14 which is detachably attached so as to close the opening 13 and has a storage recess 14a in which the isolation valve 11 is stored when the isolation valve 11 is at the open position Po. ing.

As shown in FIGS. 1, 5 and 6, the isolation valve 11 has a closed position Ps and an open position Ps.
o, and is attached to the rotating shaft 16 via the support member 15 so as to be horizontally rotatable at the cleaning position Pc.
As shown in FIG. 3, the rotating shaft 16 is rotated by a geared motor 17. FIG.
As shown in FIG. 5, the isolation valve 11 can be moved up and down for a short distance by the air cylinder 18, and is lowered when the communication valve 10 is closed by the isolation valve 11, and is raised when the communication valve 10 is opened and horizontally rotated.

As shown in FIG. 1, the lid 14 for closing the opening 13 of the valve housing 12 is provided with a rotating space reducing means, for example, a roller linear guide 19 whose one end is pivotally connected by a hinge 19a so as to be able to move forward and backward. When the screw 2 is held and closes the opening 13, the screw 2 penetrating through the screw hole 14 b
0, it is detachably screwed to the valve storage section 12.

Next, a method for producing a silicon single crystal Ig using the single crystal pulling apparatus 1 according to the present invention will be described.

As shown in FIG. 2, in order to pull a single crystal Ig using the single crystal pulling apparatus 1, a raw material polysilicon is charged into a quartz crucible 5 and heated by a heating means 7 to heat the inside of the quartz crucible 5. The raw material polysilicon is melted. When the polysilicon is completely melted, the air cylinder 18 is operated to raise the rotary shaft 16 for a short distance, and the isolation valve 11 attached to the support member 15 provided on the rotary shaft 16 is raised for a short distance. After separating the isolation valve 11 from the communication port 10, the geared motor 17 is operated to rotate the rotation shaft 16, and the isolation valve 11 is rotated by about 90 ° in the horizontal direction to retreat to the open position Po and wait. Then, the communication port 10 is opened. Next, the pulling means 9 provided in the sub-chamber 3 is operated to lower the wire 9 a in the melted silicon melt S, and the seed crystal s is immersed in the melted silicon S through the open communication port 10. With the seed crystal s immersed in the molten silicon S,
The pulling means 9 and the crucible rotation shaft 8 are rotated in opposite directions to raise the wire 9a at a low speed.

Thus, seed crystal s grows, and silicon single crystal Ig grows below seed crystal s. When the silicon single crystal Ig has grown to a predetermined length, the pulling operation is stopped, and after the pulling operation is stopped, the geared motor 17 is operated and rotated while the pulled silicon single crystal Ig is suspended above the isolation valve 11. The shaft 16 is rotated. Then, the isolation valve 11 is horizontally moved from the open position Po to the closed position Ps, and the air cylinder 18 is operated to lower the rotary shaft 16 for a short distance, so that the communication valve 10 is closed by the isolation valve 11. Thereafter, the sub-chamber 3 is returned to normal pressure while the main chamber 2 is kept in a reduced pressure state, and the single crystal Ig is taken out.

On the other hand, the inside of the pulling device 1 is at a high temperature, and SiO gas is generated from the melt S in the quartz crucible 5, and this gas diffuses upward and deposits on the inner wall of the sub-chamber 3 and the isolation valve 11 and the like. To form a film. The separation of the film causes generation of dust, and there is a problem that when the dust falls into the quartz crucible 5, the crystal Ig becomes dislocation.

Therefore, periodic cleaning of the inner wall of the sub-chamber 3 and the isolation valve 11 is required.

As shown in FIG. 1, FIG. 5 and FIG.
Is removed to leave the lid 14 in a free state, and then the lid 14 is slid horizontally along the roller linear guide 19 to approximately the middle of the length of the lid 14. Next, the lid 13 is rotated about 90 ° in the horizontal direction about the hinge 19a to open the opening 13. In opening the opening 13,
The cover 14 includes a roller linear guide 19 and a hinge 19a.
And the burden of supporting the weight is not imposed on the operator, and since the lid 14 is horizontally moved to the intermediate length, the turning radius of the lid 14 about the hinge 19a is reduced. Then, the lid 14 hits a member 21 such as a pipe or a support disposed near the silicon single crystal pulling apparatus 1,
The opening of the lid 141 is not restricted. After the valve housing 12 is opened, the rotation shaft 16 is rotated by the operation of the geared motor 17, and the isolation valve 11 is moved to about 90 degrees.
Rotate in the horizontal direction to move from the open position Po to the cleaning position Pc, and expose the isolation valve 11 outside the valve housing 12. Thereafter, the isolation valve 11 exposed outside the valve housing 12 is cleaned, and the valve housing 12 and the rotating shaft 16 are further cleaned using the opening 13. After the cleaning of the isolation valve 11, the valve housing portion 12 and the rotating shaft 16 is completed, the rotating shaft 16 is rotated by the operation of the geared motor 17, and the isolation valve 11 is rotated about 90 ° in the horizontal direction, thereby to set the cleaning position Po. To the open position Pc. Further, the cover 14 is rotated about 90 ° horizontally in a direction opposite to the opening direction around the hinge 19 a so that the cover 14 approaches the opening 13, and the cover 14 is moved inside the roller linear guide 19. To move the opening 1 with the lid 14 so that a part of the isolation valve 11 is stored in the storage recess 14 a of the lid 14.
After closing the cover 3, the lid 14 is attached to the valve storage section 12 with the screw 20. Since a part of the isolation valve 11 is housed in the housing recess 14a, the valve housing 12
Can be miniaturized, and a silicon single crystal pulling apparatus 1
Can also be small.

The rotation space reducing means may be a slide linear guide system other than the roller linear guide 19 system described above, and the cover body is divided into two parts at the intermediate portion, and each of them is airtightly integrated with a hinge. The lid may have a bent shape, and the lower portion of the lid may be pivotally connected so that the lid can be pivoted downward.

[0027]

According to the present invention, the rotation space of the lid can be reduced, so that the cleaning of the isolation valve is facilitated, and dust caused by the separation of the SiO ₂ film falls into the quartz crucible. Thus, there is no possibility that dislocations are generated in the silicon single crystal Ig, which contributes to an improvement in productivity of the silicon single crystal.

The rotation space reducing means comprises a hinge for pivotally connecting the lid to the bubble storage portion. The hinge is provided with a linear guide which is capable of moving the lid back and forth.
The structure is simple, the radius of rotation of the lid can be easily reduced, and the bubble storage unit and the single crystal pulling apparatus can be downsized.

The isolation valve is horizontally rotated by a rotation support arm which is rotated by a drive motor, so that the isolation valve can be easily exposed from the bubble storage portion through the opening, thereby facilitating cleaning. Become.

When the lid is on standby for the isolation valve,
By forming a storage recess for storing a part of the isolation valve, the bubble storage unit and the single crystal pulling apparatus can be downsized.

[Brief description of the drawings]

FIG. 1 is a perspective view showing an isolation valve means used in a single crystal pulling apparatus according to the present invention.

FIG. 2 is an explanatory view of a single crystal pulling apparatus according to the present invention.

FIG. 3 is a sectional view of an isolation valve means used in the single crystal pulling apparatus according to the present invention.

FIG. 4 is a side view of a lid used in the single crystal pulling apparatus according to the present invention.

FIG. 5 is an operation explanatory view of a lid used in the single crystal pulling apparatus according to the present invention.

FIG. 6 is an operation explanatory view of a lid used in the single crystal pulling apparatus according to the present invention.

FIG. 7 is an explanatory view of a conventional single crystal pulling apparatus.

FIG. 8 is a perspective view showing an isolation valve means used in a conventional single crystal pulling apparatus.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Silicon single crystal pulling apparatus 2 Main chamber 3 Subchamber 4 Isolation valve means 5 Quartz crucible 6 Graphite crucible 7 Heating means 8 Crucible rotating shaft 9 Pulling means 10 Communication port 11 Isolation valve 12 Valve storage unit 13 Opening 14 Lid 14a Storage recess 14b Screw hole 15 Support member 16 Rotary shaft 17 Geared motor 18 Air cylinder 19 Roller linear guide 19a Hinge 20 Screw 21 Member

Claims (4)

[Claims] 1. A main chamber containing a crucible for melting a semiconductor material and heating means for heating the crucible, and a sub-chamber provided with a pulling means for pulling a single crystal from the crucible by a seed crystal. A single crystal pulling apparatus having an isolation valve means for partitioning the two chambers between the two chambers, wherein the isolation valve means comprises an isolation valve for opening and closing a communication port provided between the two chambers. A valve housing portion in which the isolation valve is formed so as to be horizontally movable, an opening formed in one side wall of the valve housing so that the isolation valve can enter and exit, and a detachable so as to close the opening portion. And a lid which is pivotally attached to the valve storage portion via the lid rotation space reducing means when the opening is opened. And a single crystal pulling apparatus. 2. The rotation space reducing means comprises a hinge for pivotally connecting the lid to the valve housing, and the hinge is provided with a linear guide for holding the lid so as to be able to move forward and backward. The single crystal pulling apparatus according to claim 1. 3. The single crystal pulling apparatus according to claim 1, wherein the isolation valve is horizontally rotated by a rotation support arm rotated by a drive motor. 4. The storage device according to claim 1, wherein the lid is formed with a storage recess for storing a part of the isolation valve when the isolation valve is on standby.
The single crystal pulling apparatus according to any one of the above.