JP6710153B2 - Screw drop prevention mechanism and heat treatment device - Google Patents

Description

The present invention relates to a screw drop prevention mechanism and a heat treatment device.

Conventionally, as a device for forming a thin film on a substrate, a batch-type heat treatment for collectively forming a film on a plurality of substrates held by a substrate holder in a quartz processing container having an opening at the lower end. A device is known (for example, refer to Patent Document 1). In this apparatus, the processing container is supported by a water cooling flange having a cold water channel and a base plate. Further, a plate-shaped cover member is attached to the lower surface of the water cooling flange by using an upward screw to separate the region where the processing container is provided and the region below the processing container.

JP, 11-135448, A

By the way, the upward screw used when the plate-shaped cover member is attached to the lower surface of the water-cooled flange may be loosened due to the temperature change caused by the repeated film forming process performed in the process container. If the looseness is left unattended, the screws will drop. As a method of suppressing the loosening of the screw, for example, a method using a spring washer or a hybrid screw can be considered.

However, even when a spring washer or a hybrid screw is used, the screw may be loosened and fall due to repeated temperature changes performed in the processing container. Then, when the screws fall into the substrate or the substrate holder that is carried into the processing container, the screws are carried into the processing container together with the substrate and the substrate holder, which causes the generation of impurities.

Therefore, there is a demand for a screw drop prevention mechanism that can prevent the screw from falling even if the screw is loosened.

In order to achieve the above object, a screw drop prevention mechanism according to an aspect of the present invention fixes a plate-like member on a lower surface of a support table that accommodates a substrate therein and supports a processing container that performs a predetermined heat treatment on the substrate. A screw drop prevention mechanism for preventing the upward screw from falling, a fixing part fixed to the lower surface of the plate-like member, a position at which the fixing part supports the head of the screw from below, and It has a support member attached so as to be movable between a position where the head of the screw is not supported from below, and a movement limiting mechanism for limiting the movement of the support member.

According to the disclosed screw drop prevention mechanism, it is possible to prevent the screw from falling even if the screw is loosened.

Schematic sectional view of a heat treatment apparatus according to an embodiment of the present invention The figure for demonstrating the screw fall prevention mechanism of the 1st structural example. The figure for demonstrating the screw fall prevention mechanism of the 2nd structural example. The figure for demonstrating the screw fall prevention mechanism of the 3rd structural example. The figure for demonstrating the screw fall prevention mechanism of the 4th structural example.

Embodiments for carrying out the present invention will be described below with reference to the drawings. In this specification and the drawings, substantially the same configurations will be denoted by the same reference numerals, and redundant description will be omitted.

[Heat treatment equipment]
The heat treatment apparatus according to the embodiment of the present invention will be described. FIG. 1 is a schematic sectional view of a heat treatment apparatus according to an embodiment of the present invention.

As shown in FIG. 1, the heat treatment apparatus 1 has a substantially cylindrical processing container 2 with a ceiling whose longitudinal direction is the vertical direction. The processing container 2 is made of, for example, quartz. A lower end portion of the processing container 2 is opened to form an opening portion 18, and a flange portion 4 projecting outward is formed on the outer periphery of the opening portion 18. The flange portion 4 is supported by being fixed to the water cooling flange 50 and the base plate 52. A plate-shaped cover member 54 is attached to the lower surface of the water cooling flange 50 by using an upward screw 58. The cover member 54 is a plate-shaped member for separating the region S1 in which the processing container 2 is provided and the region S2 below the processing container 2. Further, a heat insulating material 56 is provided between the water cooling flange 50 and the outer wall of the processing container 2.

The opening 18 at the lower end of the processing container 2 can be opened and closed by a cap portion 6 made of quartz that can be moved up and down by an elevating mechanism 30. A wafer boat 8 made of quartz is placed on the cap portion 6 via a heat insulating cylinder 10. The wafer boat 8 holds a plurality of semiconductor wafers (hereinafter referred to as “wafer W”) substantially horizontally with a predetermined interval in the vertical direction. The wafer boat 8 is loaded into or unloaded from the processing container 2 as the cap portion 6 moves up and down.

A gas introduction pipe 24 for introducing a processing gas into the processing container 2 is provided on the lower side wall of the processing container 2 so as to penetrate the processing container 2. The gas introduction pipe 24 is inserted horizontally from the outside to the inside of the processing container 2, is bent into an L shape inside the processing container 2, and extends along the side wall to the ceiling portion.

An exhaust port 26 for exhausting the inside of the processing container 2 is formed on the lower side wall of the processing container 2, and an exhaust system (not shown) is connected to the exhaust port 26. The exhaust system includes an exhaust passage (not shown) connected to the exhaust port 26, a pressure control valve and a vacuum pump that are sequentially connected in the middle of the exhaust passage. The exhaust system allows the gas to be exhausted while adjusting the pressure in the processing container 2.

A heater 20 for heating the wafer W is provided on the outer peripheral side of the processing container 2 so as to surround the processing container 2. The heater 20 is arranged on the inner peripheral side of a substantially cylindrical heat insulating material 22.

In such a heat treatment apparatus, the upward screw 58 for fixing the cover member 54 to the lower surface of the water cooling flange 50 may be loosened due to the temperature change caused by the repeated film forming processing performed in the processing container 2. If the looseness is left, the screw 58 drops. As a method for suppressing the loosening of the screw 58, for example, a method using a spring washer or a hybrid screw can be considered.

However, even if a spring washer or a hybrid screw is used, the screw 58 may loosen and drop due to a temperature change caused by the repeated film forming process performed in the processing container 2. Further, when the screw 58 drops onto the wafer W or the wafer boat 8 which is in a standby state below the processing container 2 before being loaded into the processing container 2, the wafer boat 8 is placed in the processing container 2. The screws 58 are also carried in at the time of carrying in, which causes generation of impurities.

Therefore, there is a demand for a screw drop prevention mechanism capable of preventing the screw 58 from falling even when the screw 58 is loosened.

Hereinafter, a screw drop prevention mechanism according to an embodiment of the present invention that can prevent the screw 58 from falling even if the screw 58 is loosened will be described.

[Screw drop prevention mechanism]
A screw drop prevention mechanism according to the embodiment of the present invention will be described. The screw drop prevention mechanism according to the embodiment of the present invention has an upward facing structure that fixes the cover member 54 to the lower surface of the water cooling flange 50 that supports the processing container 2 that accommodates the wafer W therein and performs the predetermined heat treatment on the wafer W. The screw 58 is prevented from falling.

(First configuration example)
FIG. 2 is a diagram for explaining the screw drop prevention mechanism of the first configuration example. 2A is a schematic cross-sectional view showing the screw drop prevention mechanism, and FIG. 2B is a schematic perspective view showing the screw drop prevention mechanism.

As shown in FIGS. 2A and 2B, the screw drop prevention mechanism 60A of the first configuration example has a fixing portion 62, a support member 64, and a leaf spring 66. The fixing portion 62, the support member 64, and the leaf spring 66 are preferably made of a heat-resistant material such as metal from the viewpoint that they can be used in a region where the temperature becomes high.

The fixing portion 62 is a portion fixed to the lower surface of the cover member 54. The fixed portion 62 has a mounting portion 622 and a guide portion 624.

The mounting portion 622 is fixed to the cover member 54 with two rivets 68. As a result, even if the cover member 54 expands or contracts due to the temperature change caused by the repeated film forming process performed in the processing container 2, the attachment portion 622 does not easily come off from the cover member 54. Further, the mounting portion 622 may be fixed to the cover member 54 by welding.

The guide portion 624 is connected to the attachment portion 622 and guides the movement of the support member 64 (guide). A through hole 626 is formed in the guide portion 624. The guide portion 624 may be formed integrally with the mounting portion 622.

The support member 64 is movably attached to the guide portion 624, and is configured to support the head portion 582 of the screw 58. In the illustrated example, the support member 64 includes a first horizontal portion 642 movably attached to the guide portion 624, a vertical portion 644 extending vertically from one end of the first horizontal portion 642, and a vertical portion 644. The first horizontal portion 642 has a second horizontal portion 646 that extends in the horizontal direction from the end opposite to the first horizontal portion 642 and that can support the head portion 582 of the screw 58 from below.

The leaf spring 66 is provided on the support member 64 and restricts the horizontal movement of the support member 64. The leaf spring 66 enters the through hole 626 formed in the guide portion 624 at a position where the second horizontal portion 646 of the support member 64 supports the head portion 582 of the screw 58, so that the horizontal direction of the support member 64 is increased. It is shaped to limit movement.

The screw 58 is preferably a hybrid screw from the viewpoint that it is hard to loosen. Further, even when the cover member 54 expands or contracts due to the temperature change caused by the repeated film forming process performed in the processing container 2, the screw 58 tries to loosen the screw 58 on the seat surface of the screw 58. A stepped screw is preferable from the viewpoint that it is difficult to apply force.

As described above, the screw drop prevention mechanism 60A of the first configuration example has the fixing portion 62 fixed to the lower surface of the cover member 54, and the fixing portion 62 movably attached to the head portion 582 of the screw 58. It has a support member 64 that can be supported from below and a leaf spring 66 that limits the movement of the support member 64. Accordingly, even if the screw 58 is loosened, the support member 64 supports the head portion 582 of the screw 58 from below, so that the screw 58 can be prevented from falling.

(Second configuration example)
FIG. 3 is a diagram for explaining the screw drop prevention mechanism of the second configuration example. FIG. 3A is a schematic cross-sectional view showing a state where the screw drop prevention mechanism supports the screw, and FIG. 3B is a schematic perspective view showing a state where the screw drop prevention mechanism does not support the screw. is there.

As shown in FIG. 3A and FIG. 3B, the screw drop prevention mechanism 60B of the second configuration example enters the through hole formed in the cover member 54 to move the support member 64 in the horizontal direction. Is different from the first configuration example in that it has a leaf spring 70 that restricts the movement of the. Note that other configurations can be the same as those in the first configuration example, and thus a part of the description is omitted.

The screw drop prevention mechanism 60B of the second configuration example includes a fixing portion 62, a support member 64, and a leaf spring 70.

The leaf spring 70 is provided on the support member 64 and restricts the horizontal movement of the support member 64. The leaf spring 70 enters the through hole 542 formed in the cover member 54 at the position where the second horizontal portion 646 of the support member 64 supports the head portion 582 of the screw 58, so that the support member 64 moves in the horizontal direction. Restrict movement.

As described above, the screw drop prevention mechanism 60B of the second configuration example is fixed to the fixing portion 62 fixed to the lower surface of the cover member 54, and is movably attached to the fixing portion 62, and the head portion 582 of the screw 58 is fixed. It has a support member 64 that can be supported from below and a leaf spring 70 that limits the movement of the support member 64. Accordingly, even if the screw 58 is loosened, the support member 64 supports the head portion 582 of the screw 58 from below, so that the screw 58 can be prevented from falling.

(Third configuration example)
FIG. 4 is a diagram for explaining the screw drop prevention mechanism of the third configuration example, and is a schematic cross-sectional view showing the screw drop prevention mechanism.

As shown in FIG. 4, the screw drop prevention mechanism 60C of the third configuration example differs from the first configuration example in that it has a ball plunger 72 instead of the leaf spring 66. Note that other configurations can be the same as those in the first configuration example, and thus a part of the description is omitted.

The screw drop prevention mechanism 60C of the third configuration example includes a fixing portion 62, a support member 64, and a ball plunger 72.

The support member 64 is movably attached to the guide portion 624, and is configured to support the head portion 582 of the screw 58. The support member 64 includes a first horizontal portion 642 movably attached to the guide portion 624, a vertical portion 644 extending vertically from one end of the first horizontal portion 642, and a first horizontal portion 642 of the vertical portion 644. And a second horizontal portion 646 that extends in the horizontal direction from the opposite end and that can support the head portion 582 of the screw 58 from below. A through hole 648 is formed in the first horizontal portion 642.

The ball plunger 72 is provided so as to penetrate the cover member 54, and restricts the horizontal movement of the support member 64. The ball plunger 72 is formed so as to limit the horizontal movement of the support member 64 at the position where the second horizontal portion 646 of the support member 64 supports the head portion 582 of the screw 58.

As described above, the screw drop prevention mechanism 60C of the third configuration example is fixed to the fixing portion 62 fixed to the lower surface of the cover member 54 and movably attached to the fixing portion 62, and the head portion 582 of the screw 58 is fixed. It has a support member 64 that can be supported from below and a ball plunger 72 that limits the movement of the support member 64. As a result, even if the screw 58 is loosened, the support member 64 supports the head portion 582 of the screw 58 from below, so that the screw 58 can be prevented from falling.

(Fourth configuration example)
FIG. 5 is a view for explaining the screw drop prevention mechanism of the fourth configuration example, and is a schematic cross-sectional view showing the screw drop prevention mechanism.

As shown in FIG. 5, in the screw fall prevention mechanism 60D of the fourth configuration example, a through hole 648 is formed in the support member 64, and the through hole 648 formed in the support member 64 is dropped by its own weight. It differs from the first configuration example in that a pin 74 that can be inserted is provided. Note that other configurations can be the same as those in the first configuration example, and thus a part of the description is omitted.

The screw drop prevention mechanism 60D of the fourth configuration example includes a fixing portion 62, a support member 64, a pin 74, and a guide 76.

The support member 64 includes a first horizontal portion 642 movably attached to the guide portion 624, a vertical portion 644 extending vertically from one end of the first horizontal portion 642, and a first horizontal portion 642 of the vertical portion 644. And a second horizontal portion 646 that extends in the horizontal direction from the opposite end and that can support the head portion 582 of the screw 58 from below. A through hole 648 is formed in the first horizontal portion 642. The through hole 648 is formed at a position where the pin 74 is inserted at a position where the support member 64 supports the head portion 582 of the screw 58.

The pin 74 restricts the horizontal movement of the support member 64. The pin 74 can be inserted into a through hole 648 formed in the support member 64 by dropping by its own weight. By inserting the pin 74 into the through hole 648 formed in the support member 64, the horizontal movement of the support member 64 is restricted. The pin 74 is covered with a guide 76. This prevents the pin 74 from coming off.

As described above, the screw fall prevention mechanism 60D of the fourth configuration example is fixed to the fixing portion 62 fixed to the lower surface of the cover member 54, and is movably attached to the fixing portion 62, and the head portion 582 of the screw 58 is fixed. It has a support member 64 that can be supported from below and a pin 74 that limits the movement of the support member 64. Accordingly, even if the screw 58 is loosened, the support member 64 supports the head portion 582 of the screw 58 from below, so that the screw 58 can be prevented from falling.

〔Experimental result〕
An upward screw 58 for fixing the cover member 54 was attached to the lower surface of the water cooling flange 50 of the heat treatment apparatus described above, and the film forming process was repeated 110 times (Run) in the processing container 2. During the film forming process, the temperature of the water cooling flange 50 was 25 to 30°C, and the temperature of the cover member 54 was about 30°C. In addition, the time for one film forming process was 3 to 8 hours. On the other hand, the temperature of the water cooling flange 50 was 68.7 to 110° C. and the temperature of the cover member 54 was 100 to 220° C. while the wafer boat 8 was being unloaded and loaded. Further, the time for carrying out and carrying in the wafer boat 8 was 7 to 15 minutes.

After 110 times (Run) of film formation processing, it was confirmed whether or not the screw had dropped. As a result, the screws did not drop at all.

Although the embodiments for carrying out the present invention have been described above, the above contents are not intended to limit the contents of the invention, and various modifications and improvements can be made within the scope of the present invention.

The wafer W is an example of the substrate in the above embodiment. The water cooling flange 50 is an example of a support base. The cover member 54 is an example of a plate-shaped member. The leaf springs 66 and 70, the ball plunger 72, and the pin 74 are an example of a movement limiting mechanism.

In the above embodiment, the case where the movement restricting mechanism is the leaf springs 66, 70, the ball plunger 72 or the pin 74 has been described as an example, but the present invention is not limited to this, and the movement of the support member 64 is not limited to this. Other mechanisms may be used as long as they can limit

DESCRIPTION OF SYMBOLS 1 Heat treatment apparatus 2 Processing container 50 Water cooling flange 54 Cover member 58 Screw 582 Head 60 Screw drop prevention mechanism 62 Fixing part 622 Mounting part 624 Guide part 64 Supporting member 642 First horizontal part 644 Vertical part 646 Second horizontal part 648 Through hole 66 leaf spring 68 rivet 70 leaf spring 72 ball plunger 74 pin W wafer

Claims (11)

A screw fall prevention mechanism for fixing a plate-shaped member to a lower surface of a support table for supporting a processing container for accommodating a substrate therein and performing a predetermined heat treatment on the substrate, the screw fall prevention mechanism preventing falling of upward screws.
A fixing portion fixed to the lower surface of the plate-shaped member,
A support member movably attached to the fixing portion between a position that supports the head of the screw from below and a position that does not support the head of the screw from below ;
A movement limiting mechanism for limiting the movement of the support member,
Has,
Screw drop prevention mechanism. The fixing portion is fixed to the plate-shaped member by a rivet,
The screw drop prevention mechanism according to claim 1. The fixing portion is fixed to the plate-shaped member by welding,
The screw drop prevention mechanism according to claim 1. The support member is
A first horizontal portion movably attached to the fixed portion;
A vertical portion extending vertically from one end of the first horizontal portion;
A second horizontal portion extending horizontally from an end of the vertical portion opposite to the first horizontal portion and capable of supporting the head of the screw from below;
Has,
The screw drop prevention mechanism according to any one of claims 1 to 3. The movement limiting mechanism limits the horizontal movement of the support member at a position where the support member supports the head of the screw,
The screw drop prevention mechanism according to any one of claims 1 to 4. The movement limiting mechanism is a leaf spring,
The screw drop prevention mechanism according to any one of claims 1 to 5. The movement limiting mechanism is a ball plunger,
The screw drop prevention mechanism according to any one of claims 1 to 5. A through hole is formed in the support member,
The movement limiting mechanism is a pin that can be inserted into the through hole by dropping by its own weight,
The screw drop prevention mechanism according to any one of claims 1 to 5. The screw is a hybrid screw,
The screw drop prevention mechanism according to any one of claims 1 to 8. The screw is a stepped screw,
The screw drop prevention mechanism according to any one of claims 1 to 9. A heat treatment apparatus for performing a predetermined heat treatment on a substrate housed in a processing container,
A support for supporting the processing container,
A plate-like member fixed to the lower surface of the support base by an upward screw,
The screw drop prevention mechanism according to any one of claims 1 to 10, which prevents the screw from falling.
Has,
Heat treatment equipment.

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