JPH0653305A - Vertical heat treating device - Google Patents

Abstract

PURPOSE:To omit a dust-generating source in an upper region by arranging a stocker for storing a carrying container in a lower region within a vertical heat-treating device and further not to make complex a flow of a clean air within the vertical heat treatment. CONSTITUTION:A boat capable of mounting a plurality of wafers and being loaded into or out of a furnace 30 is arranged in a lower region 34 of a vertical heat-treating furnace 30, and wafers are transferred between the boat and a carrier 14 in this lower region. On the side of this lower region, a stocker 50 capable of storing a plurality of carriers 14 is arranged. On the side of the stocker 50, a second air filter 66 is further arranged. A side flow 6 sprayed from this second air filter 66 passes through the stocker 50 to form a flow of a clean air towards the lower region of the heat-treating furnace 30, so that the cleanness in the stocker 50 and the lower region may be held.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a vertical heat treatment apparatus for heat treating a semiconductor wafer, for example, and more particularly to a structure capable of keeping the inside of the apparatus clean.

[0002]

2. Description of the Related Art For example, in recent semiconductor manufacturing equipment, more dense processing is required as the density of elements is increased. In order to secure the yield of the dense processing, there is an increasing demand for further reducing the adhesion of impurities to the semiconductor wafer before and after the processing. Semiconductor wafer
In addition to being processed in a clean atmosphere, it is necessary to maintain the clean atmosphere in the transfer of the semiconductor wafer and its standby atmosphere. Especially, in the transfer and standby positions, downflow and side flow are performed depending on the holding state of the semiconductor wafer. Achieves clean air blowing.

An apparatus of this type is disclosed in Japanese Patent Laid-Open No. 61-11.
1524, Japanese Patent Laid-Open No. 62-146265, Japanese Utility Model Laid-Open No. 62-8.
633, Japanese Patent Laid-Open No. 62-36817, and Japanese Utility Model Laid-Open No. 64-268.
No. 33 publication and the like.

[0004]

In the case of the vertical heat treatment apparatus, in the lower region of the vertical heat treatment furnace, between the boat as the processing container loaded into the heat treatment furnace and the carrier as the transfer container. It is necessary to transfer the wafer. At this time, since the main surface of the semiconductor wafer is in a horizontal state, it is necessary to realize a side flow in the lower region of the heat treatment furnace.

On the other hand, a stocker carrying a plurality of carriers may be incorporated in the vertical heat treatment. By providing clean air to the wafers in the carrier mounted on the stocker, the cleanliness of the semiconductor wafer can be maintained before the heat treatment.

Conventionally, this type of stocker is arranged laterally of the vertical heat treatment furnace, that is, in the upper region of the vertical heat treatment apparatus. The reason is that in the lower area of the vertical heat treatment apparatus, there is little empty space for wafer transfer, carrier transfer, etc., while in the upper area of the vertical heat treatment apparatus,
This is because a relatively large space can be secured in the lateral region of the heat treatment furnace.

By the way, except for the carrier loading / unloading path to and from the stocker existing in the upper region of the vertical heat treatment apparatus, the carrier and wafer transfer paths are formed almost in the lower region of the vertical heat treatment apparatus. When the stocker is arranged in the upper area, an elevator mechanism for loading and unloading the carrier is required, and the dust source exists in the upper area. Dust generated in the upper area of the device tends to drop during the transportation of the wafer or carrier existing in the lower area of the device, and impurities tend to adhere to the wafer.

Therefore, it is preferable to dispose the stocker in a lower area inside the apparatus, but there is a wafer or carrier transfer path in the lower area of the apparatus, and an air blowing passage for cleaning the area. Considering that it is necessary to secure the above, it is not possible to secure the location of the stocker that occupies a relatively large volume unless the installation area of the vertical heat treatment apparatus is expanded. But,
Considering that the vertical heat treatment apparatus is installed in a clean room with a high cost per unit area, the expansion of the installation area increases the running cost of semiconductor device manufacturing.

Further, with respect to the adhesion of impurities to the wafer, dust is generated from the carrier and the wafer transfer machine.

That is, when a carrier or wafer transfer machine is provided for each transfer target, the number of combinations of mechanical parts increases, and the dust and dirt accumulated on the movable parts and storage parts of the mechanical parts scatter. There are more opportunities to do it.

Therefore, an object of the present invention is to arrange a stocker for storing a container for transportation in a lower region inside the apparatus to eliminate a dust source in the upper region, but to supply a clean air blowing path to an existing area. It is an object of the present invention to provide a vertical heat treatment apparatus that can minimize the expansion of the installation area by sharing the air flow path for the stocker.

Another object of the present invention is to provide a vertical heat treatment apparatus having a structure capable of suppressing dust generation inside the apparatus.

[0013]

A vertical heat treatment apparatus according to a first aspect of the present invention is capable of moving up and down between a vertical heat treatment furnace for heat-treating an object and a lower region of the heat treatment furnace and the inside of the heat treatment furnace. Yes, a processing container on which the object to be processed is provided for heat treatment, a transport container on which the unprocessed or processed object to be processed is mounted, and the processing carried out to a lower region of the heat treatment furnace A transfer machine for transferring the object to be processed between the container for transfer and the container for transfer, and a stocker arranged laterally of the lower region of the heat treatment furnace, on which a plurality of transfer containers are mounted,
An air filter having a blowout port that blows clean air from the side of the stocker toward the lower region of the heat treatment furnace through the stocker.

According to a second aspect of the present invention, there is provided the vertical heat treatment apparatus according to the first aspect, wherein the object to be treated in the transfer container mounted on the stocker and the object to be treated in the processing container are the respective containers. It is characterized in that its main surface is supported inside.

A vertical heat treatment apparatus according to a third aspect is the vertical heat treatment apparatus according to the first or second aspect, wherein the first and second transfer machines are extendable and retractable for transferring an object to be processed and a transfer container, respectively. It is characterized in that each mounting portion is supported by the same support body, and the support body is rotated or lifted at least by the same drive source.

[0016]

According to the first aspect of the present invention, the stocker for storing the transport container is arranged laterally of the lower region of the vertical heat treatment furnace. An air filter is provided further to the side of this stocker, and the clean air blown out from this air filter passes through the stocker and realizes a side flow toward the lower area of the heat treatment path, thereby achieving a side flow in two areas. The cleanliness of 1 is maintained by a single clean air flow.

According to the second aspect of the present invention, the main surface of the object to be processed in the carrying container mounted on the stocker is horizontal, and the side flow blown out from the air filter is not obstructed, and the heat treatment furnace It is possible to secure a smooth flow of the side flow toward the lower region.

According to the invention of claim 3, the object to be processed and the carrier are put together by the same support, so that the number of constituent parts can be made common and the number can be reduced.

[0019]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of a vertical semiconductor heat treatment apparatus to which the present invention is applied will be specifically described below with reference to the drawings.

1 to 3, an automatic door 16 for loading and unloading a carrier 14, which is an example of a transport container carrying a plurality of, for example, 25 semiconductor wafers 12, is provided on one side surface of an apparatus housing 10. It is provided. The wafer 12 is inserted into a wafer storage groove (not shown) provided in the carrier 14 at the time of loading and unloading, and is leaned vertically. The carrier 14 carried into the housing 10 is mounted on the input / output port 18 (for example, two carriers 14 can be mounted). The input / output port 18 is provided with a posture changing mechanism 20 to change the position of the carrier 14 by 90 ° as shown in FIG. The main surface of the wafer 12 in the carrier 14 whose position has been changed is supported in a horizontal state. First and second transfer arms 22 and 24 are provided to further carry the carrier 14 into the inside. The second transfer arm 24 can be moved up and down along the elevator 26, and the carrier 14 is placed on, for example, a transfer stage 28 provided in two stages by the vertical movement and arm drive of the second transfer arm 24. can do.

A vertical heat treatment furnace 30 is provided in an upper region inside the apparatus casing 10. The flange cap 32 for sealing the lower end opening (not shown) of the heat treatment furnace 30 is
It is provided so that it can swing and move up and down. In a region 34 below the heat treatment furnace 30, a quartz boat 36, which is an example of a processing container, is arranged. The boat 36 can be moved up and down by the boat elevator 38 over the inside of the heat treatment furnace 30 and the lower region 34 thereof.

A transfer machine 40 is provided between the transfer stage 28 and the lower region 34 of the heat treatment furnace 30. The arm 42 of the transfer machine 40 is expandable and contractible, and can be moved up and down and rotated, and the wafer 12 is transferred between the carrier 14 on the transfer stage 28 and the boat 36 unloaded by the heat treatment furnace 30. It is possible to transfer one by one or a plurality of sheets at the same time.

Further, in this embodiment, in the area other than the input / output port 18 and the transfer stage 28 inside the housing 10,
A stocker 50 is provided that can store up to eight carriers 14 in two rows and four stages. The stocker 50 is arranged laterally of the heat treatment furnace 30 so as to face the lower region 34. In this stocker 50, shelf plates 52 on which the carriers 14 can be placed are arranged at equal intervals in the vertical direction.

Next, the flow of clean air inside the apparatus casing 10 will be described.

On the top surface of the apparatus housing 10, a fresh air intake 60 is provided, for example, in a mesh shape. A first air filter 62 is provided between the air intake 60 and the input / output port 18 in the middle of the air flow path introduced from the air intake 60 into the housing 10. Therefore, the fresh air flow outside the housing 10 is introduced into the inside of the housing via the air intake port 60 and becomes a downflow, and is further placed on the input / output port 18 via the first air filter 62. A downflow of clean air is formed toward the carrier 14. here,
Before the carrier 14 loaded into the input / output port 18 undergoes 90 ° position conversion by the attitude conversion mechanism 20, the wafer 12 mounted on the carrier 14 is in a state parallel to the downflow. Therefore, the space around the wafer 12 mounted on the carrier 14 can be kept clean without obstructing the flow of the downflow, and the laminar flow state can be maintained even after passing through the carrier 14.

A floor hood 64 is provided at the bottom of the apparatus casing 10, and an air suction port 64a is provided on one side surface thereof. Therefore, the clean air that has passed through the carrier 14 on the input / output port 18 forms the airflow shown in FIG. 1 and is taken into the floor hood 64. Stocker 5
On the outside of 0, a second air filter 66 having an air outlet extending over at least the width and height of the stocker 50 is provided. The second air filter 66 is
The floor hood 64 has an air intake 66a communicating therewith.
The second air filter 66 forms an air flow inside the second air filter 66 to pass the filter to clean the air, and from the air outlet facing the stocker 50 side, the lower region of the heat treatment furnace 30 via the stocker 50. A side flow due to clean air is formed toward 34.

Here, since the main surface of the wafer 12 in each carrier 14 mounted on the stocker 50 is placed in a horizontal state, the flow of side flow is not obstructed and the flow of laminar flow is prevented. By keeping the stocker 50
It is possible to keep the air atmosphere clean in the arrangement area. In the lower region 34, which is the region inside the stocker 50, the transfer machine 40 transfers the wafer 12 between the carrier 14 on the transfer stage 28 and the boat 36 unloaded from the heat treatment furnace 30. . At this time, since the side flow is formed in the lower region 34 of the heat treatment furnace 30 during the transfer operation, even if dust is generated from the drive unit, the side flow can carry away dust and the like, It is possible to reduce adhesion of impurities to the unprocessed or processed wafer 12. Further, the transfer of the wafer 12 between the carrier 14 and the boat 36 is also performed in the horizontal state, so that the flow of the side flow in the laminar flow state is less likely to be hindered. Therefore, the side flow does not flow back toward the stocker 50, so that even if dust or the like occurs during transfer, it does not adhere to the wafer 12 in the stocker 50.

As described above, according to this embodiment, the side flow formed by the second air filter 66 can keep the stocker 50 and the lower region 34 of the heat treatment furnace 30 in a clean atmosphere. At this time, the carrier 14 arranged in the stocker 50 on the upstream side of the side flow
Is always in a relatively clean state because it has undergone a downflow at the input / output port 18 before being carried in here. Therefore, dust and the like can be prevented from being carried along the side flow from the upstream side of the lower region 34 of the heat treatment furnace 30, and the lower region 34 can be kept clean. Further, from the vertical heat treatment furnace 30, the boat 3
Immediately after unloading 6, the boat 36 and the wafers 12 mounted on the boat 36 are at a high temperature to some extent, but by forming a side flow with the stocker 50 side as the upstream side, the carrier 14 mounted on the stocker 50 is formed. The inner wafer 12 is not adversely affected by heat.

The side flow having passed through the stocker 50 and the lower region 34 has an air suction port 68a of a side hood 68 arranged at a position facing the second air filter 66.
It is taken into the side hood 68. A part of the taken-in air is guided again to the intake port 66a of the second air filter 66 via the floor hood 64, and another part is discharged to the outside via the air exhaust port 68b. By doing so, the air consumption inside the device casing 10 is reduced as much as possible, and the amount of air newly taken in from the outside through the air intake 60 is reduced, so that the air cleaning inside the device casing 10 is reduced. I am trying to maintain my degree.

As described above, according to this embodiment, the stocker 50 is
Is provided on the side of the lower region 34 of the heat treatment furnace 30,
The side flow from the second air filter 66 can also be used as the side flow in each of the above regions. By providing the stocker 50 on the side of the lower region 34 in this manner, the stocker 50 can be installed in the vertical heat treatment furnace 3 as in the conventional case.
Compared with the case where it is arranged in the upper region inside the device casing 10 which is on the side of 0, the number of driving units in the upper region inside the device casing 10 is reduced, so that there is no dust source in the upper region, The cleanliness inside the entire apparatus housing 10 can be improved. In order to carry the carrier 14 in and out of the stocker 50, a carry-in / carry-out path 70 (see FIG. 2) is formed in the vicinity of the lower region 34 where the boat 36 is loaded and unloaded. In this case, the carrier 14 may be loaded into and unloaded from the stocker 50 when the wafer 12 is not transferred between the boat 36 and the carrier 14, that is, after the boat 36 is loaded into the heat treatment furnace 30.
By doing so, since the side flow is always formed from the second air filter 66, the dust generated when the carrier 14 is carried in and out of the stocker 50 flows along the side flow, and at this time, the boat is in the lower region 34. Since there is no 36, impurities do not adhere to the wafer 12 mounted on the boat 36.

The present invention is not limited to the above embodiment, and various modified embodiments are possible within the scope of the gist of the present invention. According to the above-described embodiment, the fresh air taken in from the air inlet 60 first passes through the carrier 14 on the input / output port 18, and then this air is taken into the second filter 66, and the stocker 50 and the heat treatment furnace. It was also used to form the side flow in the lower region 34 of 30. However, it is not always necessary to use the downflow in the input / output port 18 and the sideflow air source in the lower region 34 in common.
The air filter 66 may be provided with an independent air supply passage.

As the structure of the transfer machine used in the above embodiment, for example, the structure shown in FIG. 4 can be adopted.

The transfer machine 400 shown in FIG. 4 is provided with a function of carrying a carrier between the input / output port and the stocker and carrying in / out a wafer between the stocker and the boat. Is different from the transfer machine shown in the above embodiment. In FIG. 4, the same components as those shown in FIGS. 1 to 3 will be described using the same reference numerals.

That is, the transfer machine 400 is provided with the arm 402 as in the above-mentioned embodiment, and the arm 402 is provided.
Are provided on the support 404.

Then, for example, a plurality of forks 402A for mounting the wafer 12 on one side of the extension direction of the arm 402, and a mounting for mounting the carrier 14 on the other side of the extension direction of the arm 402. A mounting plate 402B is provided. In the transfer machine 400, the support 404 supporting the arm 402 is rotated and lifted, and the arm 402 is rotated and lifted by, for example, reciprocating drive from the support 404 itself or reciprocating drive by the support 404. The carrier 14 or the wafer 12 can be loaded / unloaded to / from the input / output port 18 (see FIG. 2), the stocker 50, and the boat 36 depending on its operating state.

Further, in the operation of the transfer machine 400, the raising and lowering operation is carried out in order to place the carrier 14 on the shelf plate 52 of the stocker 50 and to place the wafer 12 at a predetermined position on the boat 36. Therefore, the elevating stroke of the transfer machine 400 is such that the amount of wafers 12 corresponding to the height of one step of the shelf plate 52 of the stocker 50 and the number of wafers 12 taken out from the carrier 14 can be collectively carried into the boat 36. The amount is selected according to the case of loading one wafer. In addition,
When the raising / lowering function is set on the stocker 50 side, the raising / lowering by the transfer machine 400 when carrying in / out the carrier 14 is not performed.

A boat fall prevention device 410 is provided above the rod supporting plate located on the upper surface of the boat 36. The boat falling prevention device 410 includes an arm that can be attached to and detached from a protrusion provided on the rod support plate, and prevents the boat 36 from tilting by pressing the rod support plate by the arm when the boat 12 is carried out. It has become. Further, an automatic shutter 420 is provided near the lower end opening of the vertical heat treatment furnace 30, and swings and moves up and down as shown in the figure to prevent heat release from the lower end opening of the furnace 30 after the boat 36 is carried out. There is.

In the vertical heat treatment apparatus equipped with the transfer machine 400 having such a structure, when the carrier 14 is taken out from the input / output port 18, the arm 402 of the transfer machine 400 is extended and the carrier mounting plate 402B is used as a carrier. Insert on the bottom. Then, when the arm 402 slightly moves up to float the carrier 14, it is contracted in this state and rotated toward the stocker 50. When the arm 402 faces the stocker 50, the arm 402 is moved up and down according to the position of the shelf plate 52 on which the carrier 14 is to be mounted, and the carrier mounting plate 402B is extended again at the lifted position to mount the stocker 50 on the mounting table. The carrier 14 is placed on the shelf plate 52 of the stocker 50 by positioning the carrier 14 on the top and lowering it slightly.
If the stocker 50 side is a type that moves up and down,
The arm 402 is not moved up and down, but only rotated and expanded / contracted toward the stocker 50.

On the other hand, when the wafer 12 in the carrier 14 is loaded from the stocker 50 toward the boat 36, the transfer machine 400 rotates to make the fork 402A face the carrier 14. Then, the plurality of forks 402A are simultaneously extended to insert the forks 402A into the lower surface of the wafer 12 in the carrier 14, and the plurality of wafers are placed on the boat 36 by the same operation as the loading / unloading of the carrier 14. When the wafers 12 are loaded into the boat 36, the lift amount of the forks 402A is determined according to the number of wafers 12 loaded simultaneously.

According to the structure provided with such a transfer machine,
Since the carrier can be loaded and unloaded with only one transfer machine, the structure of the loading and unloading mechanism can be simplified.

[0041]

As described above, according to the present invention, the stocker for storing the transport container is arranged between the lower region of the vertical heat treatment passage and the air filter for side-flowing the passage. While the number of dust generating sources in the upper area of the apparatus is reduced, the side flow can be used as a means for blowing clean air to the two areas, and the clean air blowing passage in the vertical heat treatment apparatus is complicated. It is possible to keep the installation area of the device to a minimum.

Further, according to the present invention, the arm having the object to be processed and the carrier mounting portion is provided, and the arm can be supported by the same support and driven by the same drive source. It is possible to simplify the loading / unloading structure for the processing body and the carrier and reduce the chances of dust generation from the component parts.

[Brief description of drawings]

FIG. 1 is a schematic perspective view for explaining a flow of clean air in a vertical semiconductor heat treatment apparatus to which the present invention is applied.

FIG. 2 is a schematic perspective view for explaining a drive member in the vertical heat treatment apparatus shown in FIG.

FIG. 3 is a schematic explanatory view of the inside of the vertical heat treatment apparatus shown in FIG. 1 viewed from the side.

FIG. 4 is a schematic perspective view for explaining a modified example of the driving member in the vertical heat treatment apparatus according to the present invention.

[Explanation of symbols]

 10 Equipment Housing 12 Semiconductor Wafer (Processing Object) 14 Carrier (Conveying Container) 30 Vertical Heat Treatment Furnace 34 Lower Area 36 Boat (Processing Container) 40 Transfer Machine 50 Stocker 66 Second Air Filter 400 Transfer Machine 402 arm 402A wafer mounting fork 402B carrier mounting plate 404 support

Claims (3)

[Claims] 1. A vertical heat treatment furnace for heat-treating an object to be treated, and a vertical region between the lower region of the heat treatment furnace and the inside of the heat treatment furnace can be moved up and down, and the object to be treated is mounted for heat treatment. A processing container, a transfer container carrying the unprocessed or processed object to be processed, and an object to be processed between the processing container and the transfer container carried out to a lower region of the heat treatment furnace. A first transfer machine for transferring, a stocker arranged laterally of a lower region of the heat treatment furnace, on which a plurality of the transfer containers are mounted, and a second transfer device for transferring the transfer containers toward the stocker And a air filter provided with a blowout port that blows clean air from the side of the stocker toward the lower region of the heat treatment furnace from the side of the stocker. Heat treatment equipment. 2. The object to be processed in the transport container mounted on the stocker according to claim 1,
The object to be treated in the processing container is supported in each of the containers with its main surface being horizontal. 3. The mounting device according to claim 1 or 2, wherein the first and second transfer machines each have a retractable mounting part for transferring the object to be processed and a transfer container, and each mounting part. Are supported by the same support, and the support is rotated or lifted at least by the same drive source.