JPS62209817A - Transfer system in clean room - Google Patents

Abstract

PURPOSE:To sharply reduce the cost of construction, equipment and maintenance of a clean room and further to save man power, by providing a plurality of semiconductor manufacturing apparatuses, a tube, a vehicle, stations, SMIF arms and blowers. CONSTITUTION:A plurality of semiconductor manufacturing apparatuses 20 whose upper part is covered with a sealing cover provided with a clean air supplying device, a tube 30 disposed between these apparatuses in a plurality, a vehicle 31 moving through the tube 30 while holding an SMIF pod 24, at least a pair of stations 32 and 33 branching from the tube 30, SMIF arms 23 interposed between these stations 32 and 33 and the semiconductor manufacturing apparatuses 20 and conducting delivery of wafer cassettes between the SMIF pod 24 and the semiconductor manufacturing apparatuses 20, and blowers 34 making the pressure in the tube 30 negative to transfer the vehicle 31 through the tube 30, are equipped. Thereby the cost of construction, equipment and maintenance of a clean room is reduced sharply, the room is automated to save man power, and a yield of products is increased.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a clean room transfer system used for transporting wafer cassettes between semiconductor manufacturing apparatuses in the field of semiconductor manufacturing such as VLSI and ■C.

"Prior Art 1. As is well known, a large amount of dust is generated in the manufacturing process of semiconductor devices, especially in the pre-process of forming circuit elements on semiconductor wafers, and during the transfer of wafers between manufacturing equipment.
The cleanliness of the working atmosphere is directly linked to product yield.

Generally, in order to maintain a highly clean working atmosphere for this type of semiconductor device, a partially laminar flow clean room as shown in FIGS. 7 to 9 is often used.

In FIG. 7, the reference numeral indicates a clean room that is separated from the outside world by an outer partition wall l, and a central passage section 2 is provided in the center of this clean room.
A plurality of passage areas 3, 3 .・
... and device maintenance areas 4, 4°... are arranged alternately through the back panel 5, and the passage area 3.3. . . . Equipment area 3a, 3 where semiconductor manufacturing equipment is installed on both sides of the interior.
It has a so-called ``pay method J'' layout, in which a... is provided.

As shown in FIG. 8, an automatic transport device 6 is installed on the ceiling of the central passageway 2 to transport semiconductor wafers along this passageway to each device area 3a, 3a, . . . . The device region 3a, 3a, . . . includes semiconductor manufacturing devices 7, 7, . . . corresponding to each semiconductor manufacturing process. ... are installed, and the semiconductor wafers or the semiconductor devices 7, 7. ...
The processing is performed in the sequential device area 3a, 3a, .
By being transported to ..., the manufacturing process is progressed sequentially.

Further, from the central passage section 2 to the passage section areas 3, 3 . Near the entrance to each device area 3a, 3a,...
- A stocker 8 for temporarily storing semiconductor wafers waiting for processing between them, and a stacker crane 9 for transferring semiconductor wafers between the stocker 8 and the automatic transfer device 6 are provided. There is.

Furthermore, as shown in FIG. 9, semiconductor manufacturing equipment 7.7. Track IO laid along...
Automatic transfer robot 1 for wafer cassettes moving above
1 is arranged. Furthermore, the main air conditioner (
An air supply section 14, 14.14 is provided which communicates with the air supply duct 12 extending from the air supply duct 12 (not shown), from which purified air passes through the ULPA filter (or HEPA filter) 13 and flows into the passage section. It is supplied to the area 3 and the device area 3a. The clean air supplied indoors is then supplied to the perforated floor (
grating, etc.) 15, passes through the free access floor 16 to reach the equipment maintenance area 4, and is then circulated back to the supply air supply section 14 by the air conditioner 17, thereby maintaining the room at a predetermined level of cleanliness. I try to do that.

However, in such partially laminar flow clean rooms, it is necessary to keep the entire room clean, so it is necessary to install an air supply section in the ceiling, or to use the floor as an effective floor and install a raised floor under the floor. At the same time, the layout of semiconductor manufacturing equipment has a special shape (for example, pay method), which requires a special building with a large indoor space, as well as clean room air purification equipment and wafer cassette transportation. Ancillary equipment such as equipment has become large-scale, and its construction and equipment costs have become enormous.Also, working tools have come to be carried out in passageways and equipment storage areas. However, there is a problem in that there is a limit to the cleanliness that can be maintained, leading to a decrease in product yield.

A clean room using an SMIF system is known as a solution to such problems.

As shown in FIG. 10, the main parts of this SMIF system include a semiconductor manufacturing equipment 2o, an airtight cover 21 covering the top of the equipment, and a high-performance filter and a blower attached to the top of the airtight cover 21. Air supply device 2
2 and a SMIF arm 23 for setting the wafer cassette at a predetermined position in the visiting semiconductor manufacturing equipment 20, and when setting the wafer cassette in the semiconductor manufacturing equipment 2o, A predetermined number of wafers are placed in the SMIF pod 24, which is an airtight container to isolate them from the outside air, and placed on the top of the SMIF arm 23, with the wafer cassette inside being deafened. Then, it is set in the semiconductor manufacturing equipment 20. Also,
The wafer that has undergone the processing steps in the semiconductor manufacturing equipment 20 is stored in a wafer cassette, then taken into the SMIF arm, and then the SMIF arm placed on top of the wafer cassette.
It can be stored inside the IF' pod 24 without being exposed to outside air. Then, the SMIF pod 24 is carried by a worker 25 to a semiconductor manufacturing device (not shown) for the next manufacturing process, and then placed again on a SMIF arm (not shown) attached to the semiconductor manufacturing device. Then, the wafer is processed in the semiconductor manufacturing equipment in the same manner as the process described above.

Therefore, in this SMIF system, regardless of whether it is being processed within the semiconductor manufacturing equipment or being transported by workers,
The wafer is isolated from the outside air and its surface is covered with clean air, making it possible to maintain a high product yield even if the cleanliness level in the clean room is 1000 to too high. As a result, the clean room does not require a special building with a large indoor space, and it can be constructed in a room of the same size as a general factory building. The construction cost, equipment cost, and maintenance cost can be significantly reduced. Additionally, workers can work in conditions similar to those in a normal room, wearing normal work clothes, and are more comfortable than in conventional clean rooms.

``Problems to be solved by the invention'' However, in clean rooms using the aforementioned SMIF system, workers are now responsible for transporting wafers between semiconductor manufacturing equipment and setting SMIF pods on SMIF arms. Therefore, their complete automation has been awaited.

The present invention has been made to satisfy the above requirements, and therefore significantly reduces the construction cost, equipment cost, and maintenance cost of a clean room, and further automates the transfer of wafers between semiconductor manufacturing equipment and the setting of SMIF pods. To provide a clean room transfer system capable of eliminating human intervention to save labor, increase product yield, and efficiently operate an SMIF system to reduce product costs. It is an object.

"Means for Solving the Problems" In order to solve the problems described above, the present invention provides a plurality of semiconductor manufacturing apparatuses whose tops are covered with airtight covers equipped with clean air supply devices, and a plurality of semiconductor manufacturing apparatuses having A tube disposed between the tube, a vehicle that moves within the tube while holding an SMIF pod, which is a sealed container for a wafer cassette, and a vehicle for transferring and timing the vehicle between the tube and the semiconductor manufacturing equipment. at least a pair of stations branching from the tube, and intervening between the station and the semiconductor manufacturing equipment iη, the SMI
It is characterized by a SMIF' arm that transfers wafer cassettes between the F-board and semiconductor manufacturing equipment, and a vehicle that creates negative pressure in the tube.

In this case, the station and the blower may be connected to each other by piping via a solenoid valve, a stopper may be provided near the branching part of the tube from the station, and the vehicle may be connected to the station by connecting the vehicle to the station and the SMI.
It is desirable to provide a lifting device for raising and lowering between the F-arm and the F-arm.

"Example" Hereinafter, the present invention will be described in detail with reference to the drawings. Figures 1 to 5 and Figure 10 show an embodiment of the present invention, and in these figures, the same elements as those in the SMIF system shown in Figure 1O are designated by the same reference numerals. , and the explanation thereof will be omitted.

FIG. 1 is a plan view showing an outline of the clean room transfer system of the present invention, and in the figure, reference numeral 20 denotes semiconductor manufacturing equipment for each of various processes, the upper part of which is covered with an airtight cover 21 equipped with a clean air supply device 22. l]-Sled, 2nd place of ＾ has a new madder red mask, -bu 30 installed. Inside this tube 30, the SMfF pod 24 is held (fourth
(see figure), a vehicle 31 is designed to move, and between the tube 30 and various semiconductor manufacturing equipment 20 there is a load-side station 32 and an unloading station for transporting the vehicle 31 therebetween or making it standby. A load side station 33 is provided branching off from the tube 30 at right angles, and a station 33 on the load side is provided between the stage type station 32 and the semiconductor manufacturing equipment 20. A SMIF arm 23 is provided for transferring wafer cassettes. Further, a blower 34 is attached to both ends of the tube 30 to move the vehicle 3I within the tube 30 by creating a negative pressure inside the tube 30.
and the stations 32 and 33 are communicated via a solenoid valve 35 and a pipe 35a. Also, tube 30
A partition plate 36 that can be opened and closed is attached to the interface between the station 32 and the stations 32 and 33.

At a predetermined position on the side of the tube 30 (position corresponding to each station), as shown in FIG.
A detector 30a is attached to detect the passage of the station, and a pair of stoppers 37 that can be tipped over are provided at the bottom near the branching points with the stations 32 and 33.

Furthermore, a hook-type lifting device 38 is provided at the top of the station 33 to raise and lower the vehicle 3I between the station 33 and the SMIF arm 23, and a hook-type lifting device 38 is provided at the bottom of the station 33 at a position corresponding to the SMTF arm 23. A freely adjustable bottom cover 39 is attached, and stoppers 37 are provided on both sides of the bottom cover 39 to allow it to fall over.

Since the orientation of the SMIF pod 24 needs to be changed for each type of semiconductor manufacturing equipment, the bottom cover 39 has a turntable function as shown in FIG. A rotary table 39b formed in the center and a support section 3 that rotatably supports the rotary table 39b on the bottom cover body 39a.
9c and a drive unit 39e that drives the rotating table 39b via a rotating gear 39d. Note that the part where the hanging line of the lifting device 38 passes through the upper surface of the station 33 may have a structure with sufficient sealing properties, or the lifting device 38 may be provided on the ceiling inside the station 33. good.

Next, FIGS. 3 to 5 show S, which is a container for shielding a wafer cassette containing wafers from the outside air.
MIF pod 24 and tube 30 with it placed inside
3 shows a vehicle 31 transporting the interior. SMIF
The pod 24 consists of a bottom plate portion on which a wafer cassette is placed and a main body (cover) portion that covers it, which are fixed to each other during transportation. Vehicle 3! is a folded container with an opening 40 at the bottom, a plurality of rollers 4 are attached to the outer surface of the container for smooth movement inside the tube 30, and the upper part is connected to the hook of the lifting device 38. A matching hanging fitting (not shown) is provided, and a wedge 4 supporting the bottom of the SMrP pod 24 is provided near the opening 40.
2 and holding it. Then, when the vehicle 31 is placed on the upper surface of the SMIT' arm 23, the SMIF
By moving the wedge 42 up and down with a detachable device (not shown) provided on the upper surface of the arm 23,
The IF pod 24 and vehicle 31 are fixed or released.

Next, how to use the lean room transfer system described above will be explained.

(1) First, operate the blower 34 and blow the tube 30
S with negative pressure inside and a Weber cassette stored.
The vehicle 31 carrying the MIF pod 24 is moved. Then, the vehicle 31 is connected to a predetermined semiconductor manufacturing apparatus 2.
When it is detected that the vehicle 31 has passed through the detector 30a near 0, the function of the blower 34 is adjusted to decelerate the vehicle 31. wake up By doing so, the vehicle 31 stops the tube 30 by using the stopper 31 to stop the front box of the load side station 33 of the semiconductor manufacturing apparatus 20. It is slidably sandwiched inside, making it impossible to move.

(2) Next, after operating the blower 34 and switching the solenoid valve 35 to create a negative pressure state in the station 33, the partition plate 37 is opened to take the vehicle 31 into the station 33, and then the stopper 37 After setting the vehicle 31 at a predetermined position on the bottom cover 39,
Blower 34 is stopped.

(3) Next, move the vehicle 31 to the hook-type lifting device 38.
After suspending it, the bottom cover 39 is opened, and it is gradually lowered and placed on the upper surface of the SMIF arm 23.

At this time, the wedge 42 comes off, and the SMIF pod 24 is detached from the vehicle 31 and placed at a predetermined position on the upper surface of the SMTP arm 23.

(4) When the SMIF pod 24 is placed on the top surface of the SMIF arm 23, the bottom plate of the SMIF pod 24 with the internal wafer cassette placed thereon is taken into the SMIF arm 23, and then only the wafer cassette is removed. It is set in the semiconductor manufacturing equipment 20. At that time, the main body part (part of the cover) remained in a state covering the upper surface of the SMI F arm 23, and when the wafer was taken into the wafer cassette or the S M I F arm 23, the S M Dust does not enter into the IF arm 23 and contaminate the wafer.

(5) When the wafer cassette is set in the semiconductor manufacturing equipment 20, the wafers are taken out one by one from the wafer cassette and processed in the semiconductor manufacturing equipment 20. The SMI is stored in the wafer cassette and is now on the unloading side.
By performing the above (3×4) process in reverse using the F arm 23, the vehicle 31 carrying the SMI F pod 24 is taken into the unloading station 32. At that time, while the wafers are being processed in the semiconductor manufacturing equipment 20, the SMI containing the empty wafer cassettes is
The vehicle 31 carrying the F-pod 24 is moved to the SMIF arm 23 on the unloading side of the semiconductor manufacturing equipment to which it should proceed next.
After moving the empty wafer cassette to the unload position of the semiconductor manufacturing apparatus 20, the SMIF arm sets the empty wafer cassette to the unload position of the semiconductor manufacturing apparatus 20.

(6) When the vehicle 31 integrated with the SMIF pod 24 containing the wafer cassette containing processed wafers is taken into the unloading station 32, the blower 34 is operated to move the inside of the tube 30. is made negative pressure, the partition plate 36 is opened, and the vehicle 31 is moved into the tube 30, and then the steps (1) to 5) are repeated, whereby the semiconductor manufacturing apparatus 20 in the successive steps is The wafers are transferred to the wafer and processed to complete the product.

As mentioned above, while the wafers housed in the wafer cassette are moving within the tube 30 and stations 32 and 33, they are housed in the SMrF pod 24 and isolated from the outside air.
2.3 The inside of the tube 30 may be as clean as a normal room, and furthermore, a small amount of outside air may enter the tube 30, or the flesh surface of the tube 30 may be severely damaged.
- The wafer will not be contaminated even if dust is generated inside the tube 30 by climbing up the slope. Therefore, the tube 30 does not require the use of expensive materials or high-precision machining to improve the degree of sealing and internal finish, and the manufacturing cost can be reduced. Further, by providing the detector 30a and the stopper 37 on the tube 30, the vehicle 31 can be stopped in front of any station, and the blower 34 only needs to be provided at both ends of the tube 30, and the wafer Continuous transport of cassettes becomes possible.

Further, since the tube 30 does not require additional equipment such as a cleaning device, the semiconductor manufacturing apparatus 20 can be laid out freely and inexpensively indoors.

As a result, a clean room using the system of the present invention does not require a special building with a large indoor space.
It can be constructed even in an indoor room of the same size as a general factory building, and the incidental equipment of the clean room can be simplified, making it possible to significantly reduce the construction cost, equipment cost, and maintenance cost.

Furthermore, wafer transfer between semiconductor manufacturing equipment and SMIF
By automating the setting of pods, it is possible to save labor by eliminating human intervention, and also to increase the product yield even more than when transporting SMIF pods manually, and to operate the SMrF system efficiently. Avoid,
Product costs can be reduced.

In the above embodiment, when moving the tool within the tube 30, the SML and F pod 24 are mounted on the vehicle 3I, but as shown in FIG. Instead, rollers 41 may be directly attached to the outer surface of the SMIF pod 24 to move it. Additionally, SMIF pod 24 was installed at station 32.33.
A guide may be provided between the station 32, 33 and the SMIF arm 23 in order to stabilize the station 32, 33 or to change its orientation when moving between the station 32, 33 and the SMIF arm 23.

"Effects of the Invention" As explained above, the present invention includes a plurality of semiconductor manufacturing devices, a tube disposed between the semiconductor manufacturing devices, a vehicle that moves within the tube while holding an SMIF pod, A station for transferring and waiting this vehicle between the tube and the semiconductor manufacturing equipment, and an S
The clean room is equipped with an SMIF arm that transfers wafer cassettes between the MIF pod and semiconductor manufacturing equipment, and a blower that moves the vehicle within the tube, eliminating the need for a special building with a large interior space. , semiconductor manufacturing equipment can be placed freely, construction can be carried out indoors on the same scale as in a general factory building, ancillary equipment is simplified, construction costs, equipment costs and maintenance costs are significantly reduced. Furthermore, it is possible to reduce human intervention, save labor, and increase product yield, as well as efficiently operate the SMIF system and reduce product costs.

[Brief explanation of drawings]

1 to 5 show an embodiment of the present invention. FIG. 1 is a plan view showing an overview of the clean room transfer system of the present invention, and FIG. 2 is a perspective view showing the vicinity of the station. Figure 3 is a perspective view of the vehicle, Figure 4 is a partially sectional front view showing the SMIF pod mounted on the vehicle, Figure 5 is a side sectional view showing details of the bottom cover of the station, and Figure 6. shows another embodiment and shows a state S in which a roller is directly attached.
Perspective views of the MIF pod, Figures 7 to 9 are diagrams showing conventional partially laminar flow clean rooms, Figure 7 is a plan view of a clean room with a pay-type layout, and Figure 8 is a view from the central passageway. A perspective view of the passageway area;
FIG. 9 is a perspective view of the passage area where the semiconductor manufacturing equipment is installed, and FIG. 1O is the SMI used in the conventional and part of this embodiment.
It is a perspective view showing a clean room of F system. 20... Semiconductor manufacturing equipment, 2! ... Seat cover, 22 ... Clean air supply device, 23.
...SMIF arm, 24...SMIF
Pod, 30...Tube, 31...
Vehicle, 32.33...Stay-L-RiriC
------, Teitou ni a... Piping, 3
7...stopper, 38...lifting device. Figure 8 Figure 6 Figure 4 Diagram 4 Figure 5

Claims (4)

[Claims] (1) A plurality of semiconductor manufacturing equipment whose upper portions are covered with airtight covers equipped with clean air supply devices, a tube disposed between the plurality of semiconductor manufacturing equipment, and a sealed container for wafer cassettes inside the tube. a vehicle that moves while holding a SMIF pod; at least a pair of stations branching from the tube for transferring and waiting the vehicle between the tube and the semiconductor manufacturing equipment; and a station and the semiconductor manufacturing equipment. A SMIF arm is provided between the SMIF pod and the semiconductor manufacturing equipment to transfer wafer cassettes between the SMIF pod and the semiconductor manufacturing equipment, and a blower is provided to move a vehicle within the tube by creating a negative pressure inside the tube. Clean room transfer system. (2) The clean room transfer system according to claim 1, wherein the station and the blower are communicated with each other by piping via a solenoid valve. (3) The clean room transfer system according to claim 1 or 2, characterized in that a stopper is provided near the branching point between the tube and the station so as to be able to fall freely. (4) The clean room transfer system according to any one of claims 1 to 3, wherein the station is provided with a lifting device for raising and lowering the vehicle between the station and the SMIF arm.