JP3540978B2 - Heat treatment equipment for semiconductor wafers - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a heat treatment system for semiconductor wafer, in which maintenance/inspection work can be carried out easily and efficiently. SOLUTION: A maintenance/inspection opening 22 is made in a barrier wall 5 sectioning a load chamber 3 and a carrying chamber 4. The opening 22 is closed by a maintenance/inspection door 23, which can be opened toward the load chamber 3. The maintenance/inspection door 23 is provided with an opening 25 for transferring a semiconductor wafer and an isolation door 26 for opening/ closing the opening 25.

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a semiconductor wafer heat treatment apparatus used for forming an oxide film on a surface of a semiconductor wafer or performing processing such as diffusion, and particularly, to facilitate maintenance and inspection work in the apparatus. Related to technology.
[0002]
[Prior art]
When forming a silicon oxide film (SiO ₂ ) or the like on the surface of a semiconductor wafer, for example, a heat treatment apparatus as shown in FIGS. 5 and 6 is used.
This heat treatment apparatus is provided with a vertical heat treatment furnace 2 having a heater, a quartz process tube, and the like for performing heat treatment such as oxidation and diffusion on a semiconductor wafer in a housing 1. A load chamber 3 for transferring semiconductor wafers to a wafer boat 7 is provided below. Further, a transfer chamber 4 for transferring a cassette containing semiconductor wafers is provided adjacent to the load chamber 3, and the load chamber 3 and the transfer chamber 4 are partitioned by a partition wall 5.
[0003]
In the load chamber 3, a wafer boat 7 for holding semiconductor wafers, a lift mechanism 8 for introducing the wafer boat 7 into a process tube of the heat treatment furnace 2, and a semiconductor boat in the transfer chamber 4 7 is provided with a wafer transfer robot 10 for transferring the wafer to the load chamber 7 and a clean unit 11 for supplying clean air into the load chamber 3. The load chamber 3 is provided with a door 12 for maintenance of the load chamber at an end of a wall opposite to the transfer chamber 4 (right end side in the figure).
[0004]
On the other hand, in the transfer chamber 4, a cassette station 14 for temporarily holding a cassette containing a large number of semiconductor wafers at the time of loading and unloading, and a cassette station 14 for holding and selecting a cassette containing semiconductor wafers to be heat-treated. And a transfer robot 16 for transferring the cassette held in the cassette station 14 to the turntable 15. Further, the transfer chamber 4 is provided with a door 17 for loading and unloading a cassette placed on a wall end opposite to the load chamber 3 (left side in the figure).
[0005]
An opening 20 for transferring the semiconductor wafer in the transfer chamber 4 to the load chamber 3 and an isolation door 21 for opening and closing the opening 20 are provided in the partition wall 5 for partitioning the load chamber 3 and the transfer chamber 4. Have been.
The wafer transfer opening 20 allows the semiconductor wafer held in one cassette on the turntable 15 to be loaded into the load chamber 3 by the wafer transfer robot 10 provided on the load chamber 3 side. It is set to the minimum size. The reason why the opening 20 for transferring the wafer is set to the minimum size is to reduce the size of the isolation door 21 and to easily obtain the pressure difference between the load chamber 3 and the transfer chamber 4. In order to The isolation door 21 is provided inside the load chamber 3 of the partition wall 4, and slides left and right along a guide rail by driving an air cylinder (not shown), thereby opening the wafer transfer opening 20. It is configured to open and close.
The size of the wafer transfer opening 20 is set to, for example, about 240 mm in width and about 290 mm in height.
[0006]
In the heat treatment apparatus having such a configuration, in order to heat-treat a semiconductor wafer, first, the carry-in / out door 17 is opened, and a cassette on which a large number of semiconductor wafers are placed is sent to the cassette station 14 in the transfer chamber 4. Is temporarily stocked. Next, the cassette is transferred from the cassette station 14 onto the turntable 15 by the transfer robot 16, and the turntable 15 is rotated and a predetermined cassette is selectively arranged so as to face the opening 20 for wafer transfer.
[0007]
Thereafter, the isolation door 21 is opened, and the semiconductor wafer set in one cassette on the turntable 15 by the wafer transfer robot 10 is taken into the load chamber 3 through the wafer transfer opening 20. The wafer is transferred onto the wafer boat 7. When a large number of semiconductor wafers are placed on the wafer boat 7 in this way, the isolation door 21 is closed, and the wafer boat 7 is lifted by the lift mechanism 8 and introduced into the heat treatment furnace 2, A predetermined heat treatment is performed.
When the heat treatment is completed, the wafer boat 7 is lowered by the lift mechanism 8 and taken out of the heat treatment furnace 2. After the temperature of the semiconductor wafer is lowered to a predetermined temperature, the semiconductor wafer is carried out of the load chamber 3 through the transfer chamber 4 to the outside of the heat treatment apparatus through the reverse procedure.
[0008]
[Problems to be solved by the invention]
However, the conventional heat treatment apparatus described above has the following problems.
That is, when performing maintenance and inspection of the turntable 15 provided in the transfer chamber 4, even if the carry-in / out door 17 of the transfer chamber 4 is opened, the distance from the position to the innermost turntable 15 is maintained. In addition, since various devices such as the cassette station 14 and the transfer robot 16 are provided, the worker cannot reach the turntable 15 for maintenance and inspection. On the other hand, since a somewhat larger internal space is secured in the load chamber 3 than in the transfer chamber 4, the door 12 for maintenance of the load chamber and the isolation door 21 are both opened, and the wafer is opened from the inside of the load chamber 3. Through the transfer opening 20, maintenance and inspection of the turntable 15 can be performed.
[0009]
However, the opening 20 for transferring the wafer has a minimum necessary size such that the semiconductor wafer set in one cassette on the turntable 15 can be taken into the load chamber 3. Even if the isolation door 21 is fully opened, even if the opening area of the wafer transfer opening 20 is extremely small and the turntable 15 can be maintained and inspected from the load chamber 3 side, the operation is difficult and the operation is difficult. The efficiency is extremely poor.
In addition, it is conceivable to provide dedicated maintenance and inspection doors on a part of the left and right side walls of the housing 1 on the side of the transfer chamber 4. Doors for maintenance and inspection cannot be provided in any places.
[0010]
Further, in the heat treatment apparatus having the above configuration, the isolation door 21 and its driving mechanism need to be assembled to the partition 5 after the partition 5 has been constructed in view of the working space or the like. Must be done in For this reason, these isolation doors 21 and their driving mechanisms are arranged on the surface of the load chamber 3 of the partition wall 5. Therefore, there is a possibility that the atmosphere in the load chamber 3 may be contaminated, for example, fine particles may be scattered with the opening and closing of the isolation door 21.
SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problem, and a semiconductor wafer heat treatment apparatus capable of easily and efficiently performing maintenance and inspection work from a load chamber side for an apparatus provided in a transfer chamber. The purpose is to provide.
Another object of the present invention is to provide a semiconductor wafer heat treatment apparatus capable of suppressing contamination of a load chamber even when fine particles are generated when opening and closing an isolation door.
[0011]
[Means for Solving the Problems]
In order to achieve the above object, a semiconductor wafer heat treatment apparatus of the present invention is provided with a load chamber for transferring a semiconductor wafer to a wafer boat below a heat treatment furnace for performing heat treatment on the semiconductor wafer. A transfer chamber for transferring the semiconductor wafer to the load chamber is provided adjacent to the load chamber, and the load chamber and the transfer chamber are separated by a partition. In addition, a maintenance inspection opening is formed, and a maintenance inspection door that opens and closes this opening is rotatably provided on the load chamber side, and the semiconductor wafer is transferred to the maintenance inspection door. An opening for transferring from the chamber to the load chamber, and an isolation door for opening and closing the opening are provided (claim 1).
According to the semiconductor wafer heat treatment apparatus having such a configuration, by opening the maintenance inspection door, it is possible to secure the maintenance inspection opening having an opening area sufficiently larger than the wafer transfer opening. Therefore, maintenance and inspection of various devices provided in the transfer chamber from the load chamber through the maintenance and inspection opening can be performed.
[0012]
In the heat treatment apparatus, it is preferable that the isolation door is attached to a surface of the door for maintenance and inspection on the transfer chamber side (claim 2).
In this case, even if fine particles are generated with the opening and closing of the isolation door, there is no possibility that these particles will scatter in the load chamber.
[0013]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, embodiments of the present invention will be described, and features thereof will be described in more detail.
FIG. 1 is a schematic plan view of a semiconductor wafer heat treatment apparatus according to an embodiment of the present invention, as viewed from the top, and FIG. 2 is a schematic longitudinal sectional view showing a main part of the apparatus.
In FIGS. 1 and 2, parts corresponding to the conventional heat treatment apparatus shown in FIGS. 5 and 6 are denoted by the same reference numerals. That is, reference numeral 1 denotes a housing, 2 denotes a heat treatment furnace for performing a predetermined heat treatment such as formation of an oxide film on a semiconductor wafer, and 3 denotes a semiconductor wafer provided below the heat treatment furnace 2 for transferring a semiconductor wafer to a wafer boat. Reference numeral 4 denotes a transfer chamber for transferring the semiconductor wafer to the load chamber 3 side, and reference numeral 5 denotes a partition for partitioning the two chambers 3 and 4.
[0014]
Reference numeral 7 denotes a wafer boat for holding a semiconductor wafer, 8 denotes a lift mechanism for introducing the wafer boat 7 into a process tube of the heat treatment furnace 2, and 10 denotes a semiconductor wafer in the transfer chamber 4 to the wafer boat 7. Is a clean unit for cleaning the inside of the load chamber 3 by blowing clean air, and 12 is a door for maintenance of the load chamber.
Further, 14 is a cassette station for temporarily holding a cassette on which a large number of semiconductor wafers are mounted, 15 is a turntable for selecting a required cassette having semiconductor wafers to be heat-treated, and 16 is a turntable. A transfer robot 17 for transferring the cassette in the cassette station 14 to the turntable 15, and a loading / unloading door 17 for loading / unloading the cassette, the basic structure of which is shown in FIGS. It is the same as that of the device.
[0015]
A feature of the heat treatment apparatus in this embodiment is that a maintenance and inspection opening 22 is formed in the partition wall 5 that partitions the load chamber 3 and the transfer chamber 4, and this opening 22 is opened and closed toward the load chamber 3. A door 23 for maintenance and inspection is provided, and an opening 25 for transferring a semiconductor wafer and an isolation door 26 for opening and closing the opening 25 are provided on the door 23 for maintenance and inspection. That is the point.
[0016]
FIGS. 3 and 4 show a specific mounting structure of the maintenance door 23 and the isolation door 26 described above.
The partition 5 has an opening 22 for maintenance and inspection, which has a vertically long rectangular shape. The opening 22 has an opening area sufficiently larger than the opening 25 for transferring a wafer. A pair of upper and lower lift-off hinges 27 is fixed to a portion of one of the left and right edges adjacent to the opening 22 facing the load chamber 3 side. One end of the door 23 is attached so that the maintenance door 23 can be opened and closed around the lift-off hinge 27 toward the load chamber 3. A side end of the maintenance inspection door 23 opposite to the hinge attachment side is detachably fixed to the partition wall 5 by screws 29. The lower edge of the maintenance door 23 is located at a position where the lower edge does not interfere with the wafer transfer robot 10 provided below the load chamber 3 when the door 23 is opened and closed. Reference numeral 30 denotes a sealing material made of foamed silicon or the like.
[0017]
The wafer transfer opening 25 has a rectangular shape and is formed substantially at the center of the maintenance inspection door 23. Guide frames 31 are fixed to the left and right edges of the maintenance inspection door 23 adjacent to the opening 25 and facing the transfer chamber 5, respectively. Is attached.
[0018]
On the other hand, the isolation door 26 is provided on a door surface located on the transfer chamber 4 side of the maintenance and inspection door 23, and guide bars 33 are fixed to left and right side ends thereof, respectively. 33 is sandwiched between the pair of front and rear pressing rollers 32 described above. Therefore, when the isolation door 26 moves up and down, the guide bar 33 fixed thereto is slid smoothly along the guide frame 31 by the pressing roller 32. The lower end of the isolation door 26 is connected to a rodless cylinder 35. Thereby, the isolation door 26 is moved up and down along the up-down direction of the maintenance door 23, and the opening 25 for wafer transfer is opened and closed.
Incidentally, in this embodiment, the size of the opening 22 for maintenance and inspection is 950 mm in height and 400 mm in width, and the size of the opening 25 for wafer transfer is 285 mm in height. The width is 245 mm.
The isolation door 26 and its drive mechanism are arranged on the transfer chamber 4 side without any trouble by attaching the door 23 for maintenance and inspection to the partition wall 5 before attaching it to the partition wall 5. be able to.
[0019]
In the heat treatment apparatus having the above-described configuration, when heat treatment of a semiconductor wafer is performed, the isolation door 26 is slid up and down in the same manner as in the related art with the maintenance inspection door 23 closed. The transfer opening 25 is opened and closed, and the semiconductor wafer is taken in and out of the wafer transfer robot 25 through the wafer transfer opening 25.
[0020]
On the other hand, when performing the maintenance and inspection of the turntable 15, the screw 29 is loosened, the maintenance and inspection door 23 is turned toward the load chamber 3, and the maintenance and inspection opening 22 is opened. Through 22, maintenance work of the turntable 15 is performed from the load chamber 3 side. At this time, since the opened maintenance / inspection opening 22 has a sufficiently larger opening area than the wafer transfer opening 25, maintenance / inspection work can be performed more easily and more efficiently than in the past.
When performing maintenance or the like of the isolation door 26, the rodless cylinder 35, or the like, the maintenance inspection door 23 is detached from the lift-off hinge 27, and is taken out of the load chamber maintenance door 12 to the outside. Necessary parts can be exchanged or adjusted externally, so that the work is easy and the time for maintenance work can be reduced.
[0021]
In addition, since the isolation door 26 is attached to the surface of the maintenance door 23 on the transfer chamber 4 side, even if fine particles are generated as the isolation door 26 is opened and closed, the particles are loaded. There is no risk of scattering in the room 3. Therefore, it is possible to prevent a problem that the load chamber 3 is contaminated with the particles.
[0022]
【The invention's effect】
As described above, according to the semiconductor wafer heat treatment apparatus of the first aspect, by opening the maintenance / inspection door, the maintenance / inspection door has a sufficiently larger opening area than the wafer transfer opening. Since the maintenance and inspection work of the devices in the transfer chamber can be performed from the load chamber side, the maintenance and inspection work can be performed easily and efficiently as compared with the related art.
[0023]
According to the heat treatment apparatus for a semiconductor wafer according to the second aspect, since the isolation door is attached to the surface of the maintenance door, which faces the transfer chamber, fine particles are generated with the opening and closing of the isolation door. However, there is no possibility that the particles are scattered in the load chamber, and it is possible to prevent a problem that the load chamber is contaminated with the particles.
[Brief description of the drawings]
FIG. 1 is a schematic sectional view showing a heat treatment apparatus according to an embodiment of the present invention as viewed from a plane.
FIG. 2 is a longitudinal sectional view showing a main part of the heat treatment apparatus according to the embodiment of the present invention.
FIG. 3 is a front view showing a state in which a mounting structure of a maintenance inspection door and an isolation door is viewed from a transfer chamber side in the heat treatment apparatus according to the embodiment of the present invention.
FIG. 4 is a sectional view taken along line AA of FIG. 3;
FIG. 5 is a plan sectional view showing the entire conventional heat treatment apparatus as viewed from a plane.
FIG. 6 is a longitudinal sectional view of a main part of a conventional heat treatment apparatus.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Housing 2 Heat treatment furnace 3 Load chamber 4 Transfer chamber 7 Wafer boat 15 Turntable 25 Wafer transfer opening 26 Isolation door 22 Maintenance inspection opening 23 Maintenance inspection door

Claims (2)

A load chamber for transferring a semiconductor wafer to a wafer boat is provided below a heat treatment furnace for performing a heat treatment on the semiconductor wafer. In a heat treatment apparatus for a semiconductor wafer, wherein a transfer chamber is provided, and the load chamber and the transfer chamber are partitioned by partition walls.
An opening for maintenance and inspection is formed in the partition wall, and a door for maintenance and inspection for opening and closing the opening is rotatably provided on the load chamber side. An opening for transferring the wafer from the transfer chamber to the load chamber, and an isolation door for opening and closing the opening. The heat treatment apparatus for a semiconductor wafer according to claim 1, wherein the isolation door is attached to a surface of the maintenance door on a transfer chamber side.

Images