JPH0821610B2 - Method and device for storing and taking out contents of carrier box - Google Patents

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a carrier box used for transporting wafers during semiconductor manufacturing, and more specifically, it stores a wafer as a content in a carrier box. Method and apparatus for removal therefrom.

[Prior Art] As is well known, it is necessary to prevent dust from adhering to a wafer during semiconductor manufacturing. Therefore, in the conventional carrier box, clean air or an inert gas is sealed inside.

On the other hand, in recent years, a carrier box has been developed that can make a vacuum state inside (so-called “vacuum drawing”). According to a new carrier box of this type, a so-called "vacuum drawing" is performed when a wafer is accommodated in the carrier box and transferred, and the inside becomes a vacuum state.

On the other hand, when a wafer is taken out from the carrier box in a clean room or the like, if the inside of the carrier box is in a vacuum state, the carrier box remains closed due to the difference in internal and external pressures, so that the inside of the carrier box is communicated with the atmospheric pressure. There is a need. In other words, it is necessary to do so-called "vacuum break".

Therefore, the conventional carrier box is equipped with a valve for communicating the inside with a vacuum source and / or the atmosphere.

FIG. 5 shows an example of such a conventional carrier box, and the carrier box generally designated by reference numeral 1 is a door 2
And valve 3. The valve 3 connects the internal space I of the carrier box 1 to either a vacuum source (not shown) or the atmosphere, and is switchable.

In the prior art shown in FIG. 5, in order to make the boundary between the door 2 and the edge portion 1e airtight, the edge portion 1e is provided with an O-ring 4 as a sealing material. A wafer carrier 5 is housed in the internal space I of the carrier box 1, and wafers W ... Are set in the wafer carrier 5. Reference numeral 6 indicates a handle.

FIG. 6 shows a carrier box of a type different from that of FIG. Also in this prior art, the valve 3 for communicating the internal space of the carrier box 1 with either the vacuum source or the atmosphere is shown. The reference numeral 7 in FIG. 6 indicates a stopper for supporting the door 2.

[Problems to be Solved by the Invention] However, in the conventional carrier box (1), the valve (3) is indispensable, but there is a problem that the carrier box itself becomes heavy because the valve is heavy. .

Further, it is necessary to connect the valve to a vacuum source when the contents (wafers) are stored in the carrier box, and to disconnect the valve from the vacuum source when the contents are transferred. for that reason,
In actual use, it is necessary to connect and disconnect the valve, which is very complicated.

The present invention has been proposed in view of the above-mentioned problems of the prior art, and it is not necessary to have a valve in the carrier box main body, and accommodation and extraction of the contents of the carrier box that can perform vacuuming and vacuum breaking in the carrier box. It is intended to provide a method and apparatus.

[Means for Solving the Problem] According to the present invention, in the method for storing and extracting the contents of the carrier box, in which the contents are stored in or removed from the carrier box whose inside is in a vacuum state, the first door is provided. The carrier box which has the
A step of fitting from the door side of the device, a step of making a connection chamber provided inside the accommodating and extracting device and communicating with a vacuum source and the atmosphere through a valve into a vacuum state, and a step provided in the connection chamber. A step of adsorbing the arm of the storage / ejection device to the first door, a step of moving the arm together with the first door of the carrier box, a step of breaking the vacuum state of the connection chamber, and a connection of the storage / ejection device. Second part of a room
Opening the door to store the contents in the carrier box or remove the contents.

Further, according to the present invention, in a carrier box contents accommodating / discharging device for accommodating or extracting contents in a carrier box having a vacuum inside, a carrier box having a first door is replaced by a first door. From the side to hold it, a connection chamber communicating with the vacuum source and the atmosphere via a valve, and an arm provided in the connection chamber for contacting and adsorbing the first door. A suction means provided inside the arm, a lower chamber for accommodating the first door and the arm, a driving means for driving the arm, and a second chamber forming a part of the connection chamber. It includes a door and.

Here, an electromagnet means is suitable as the adsorption means, and in that case, a power source for the electromagnet means is also provided.

Further, it is preferable that the lower chamber is formed of a flexible member.

The carrier box of the present invention used in the device for storing and taking out the contents of the carrier box has a shape corresponding to the receiving part of the above-mentioned storing and taking out device in the vicinity of the first door side edge of the side wall of the main body. A fitting portion is formed and is provided at a boundary between the first door and the first door side edge portion of the side wall of the main body portion, and a sealing member for making the boundary airtight, the receiving portion and the fitting portion. And a sealing member which is provided at the boundary between and to make the boundary airtight.

Here, although it is preferable to form a stepped portion as the fitting portion, it is not necessarily limited thereto. In short,
Any shape may be used as long as it can be connected to and supported by the receiving port of the storage and ejection device. For example, it is possible to form a taper corresponding to the receiving port of the accommodating / extracting device and the fitting part, and to provide a seal member on the tapered surface. However, in that case, it is preferable that the seal member is configured so as to prevent wear and damage of the seal material due to sliding between the tapered surfaces and dust generation accompanying the wear and damage.

Here, the above-mentioned word "arm" is a general term for a means for moving the first door, and is meant to include all members having a function of moving the first door by a suction or non-contact method. .

In the method for accommodating and extracting the contents of the carrier box of the present invention, when the carrier box is conveyed after accommodating the contents, a step of closing the second door, a step of communicating the connection chamber with a vacuum source, A step of bringing the first door adsorbed by the arm of the accommodating and extracting device into contact with the carrier box; a step of opening the connection chamber to the atmosphere side; a step of releasing the arm from the first door by adsorbing the carrier box; It is preferable to perform the step of removing the fitting from the receiving port of the take-out device.

In carrying out the present invention, the device for accommodating and extracting the contents of the carrier box is provided in a wall portion of a clean room or the like, and the receiving portion is covered with an air curtain or the like to prevent dust and other contaminants from entering the receiving portion. Is preferred.

In implementing the device for storing and extracting the contents of the carrier box of the present invention, it is preferable that the flexible member forming the lower chamber is formed of, for example, a diaphragm.

Further, in the carrier box of the present invention, the seal member provided at the boundary between the first door and the main body edge is the first
The seal ring may be a seal ring provided on the door or a seal ring provided on the edge of the main body. And
The seal member provided at the boundary between the receiving port and the step may be a seal ring provided at the edge of the receiving port, or a seal ring provided at the step facing the edge. May be. In addition, it is preferable that the surface of the portion where the carrier box is fitted to the receiving portion is tapered so that the fitting and the unmounting can be easily performed.

In addition to the above, in the practice of the present invention, a series of operations from fitting the carrier box to the loading / unloading device, loading or unloading contents such as wafers, and unloading the carrier box are automatically controlled. It is possible to In that case, it is preferable to provide a central control unit and various sensors in the device for storing and extracting the contents of the carrier box of the present invention.

When the contents such as wafers are transferred by the carrier box used in the present invention, the door of the carrier box (first
It is preferable to attach a stopper for the door to the carrier box body in order to prevent the door) from being opened accidentally.

Further, in carrying out the present invention, when the wafers and the like are not housed in the carrier box, an inert gas such as nitrogen (N ₂ ) is filled, and the door (first door) is closed by the above-mentioned stopper. It is preferable to hold.

In the carrier box of the present invention, it is preferable to provide, as the fitting portion, for example, a step portion provided on a side wall of the main body portion in the vicinity of the first door side edge portion.

[Operation] According to the present invention having the above-described structure, when the contents are stored in the carrier box or the contents are taken out, the carrier box is inserted into the receiving / introducing portion of the accommodating / discharging device provided in the wall of the clean room or the like. Fit. Here, since the carrier box itself is not provided with a valve, the weight is extremely reduced, and the fitting operation itself is extremely easy as compared with the connection or disconnection operation of the valve.

Next, it is necessary to open the door of the carrier box, that is, the first door, but the inside of the carrier box is in a vacuum state and can be opened unless the pressure difference from the external pressure (atmospheric pressure) disappears. Absent. Therefore, the valve is switched to the vacuum source side so that the connection chamber provided inside the accommodating / extracting device is communicated with the vacuum source, and thus the connection chamber is evacuated to a pressure difference between the connection chamber and the inside of the carrier box. Disappear. In this state, if the arm of the storage and take-out device is adsorbed to the first door provided on the carrier box and the arm of the carrier box is moved (retracted) together with the door of the carrier box, the first door is opened. . Then, the arm is housed in the lower chamber together with the first door so that the first door and the arm do not interfere with the subsequent work.

Next, it is necessary to open the second door provided in the storage and take-out device to communicate with the clean room. However, since the inside of the connection chamber is in a vacuum state as described above, the space between the clean room interior (atmospheric pressure) There is a pressure difference. Therefore, the valve is switched to the atmosphere side to break the vacuum state of the connection chamber. As a result, there is no pressure difference between the connection chamber and the clean room, and the second door can be opened. Then, the contents may be accommodated in the carrier box or taken out from the opening of the second door.

As described above, according to the present invention, the pressure difference between the inside of the carrier box and the inside of the clean room can be eliminated and the contents can be stored or taken out without providing a valve in the carrier box. As a result, the carrier box can be significantly reduced in weight.

Furthermore, since connection and disconnection between the valve and the vacuum source side system are not required and automatic control is possible, the work of taking out or storing the contents from the carrier box becomes extremely easy.

When the carrier box is removed from the storage and take-out device, the second door is closed and the valve is connected to a vacuum source to bring the inside of the connection chamber and the inside of the carrier box into a vacuum state.
In this state, the arm is operated and moved to bring the first door adsorbed on the arm into contact with the carrier box. When the valve is switched to the atmosphere side, the connection chamber is opened to the atmosphere side while the inside of the carrier box remains in a vacuum state, and the first door is pressed against the carrier box by the pressure difference. After that, the carrier box is unmounted from the receiving part of the storage and take-out device, and is transported together with the contents.

Further, in the carrier box of the present invention, the boundary between the first door and the edge of the main body portion, the boundary between the receiving portion and the step portion, and the seal member are provided, and the seal member defines the boundaries thereof. Since it is made airtight, pressure leakage does not occur at the boundary during vacuuming and vacuum breaking as described above, and the differential pressure can be kept constant.

Here, since the seal member is not provided at the sliding portion, dust generation and seal deterioration due to sliding wear are prevented. In other words, in the carrier box of the present invention, the seal member can be provided at a place other than the above-mentioned various boundary portions, but in that case, a dustproof mechanism needs to be provided separately.

[Embodiment] An embodiment of the present invention will be described below mainly with reference to FIGS.

In FIG. 1, a carrier box generally denoted by reference numeral 12 is fitted to the storage / removal apparatus generally denoted by reference numeral 10, and the storage / removal apparatus 10 is provided on the clean room wall portion CW. Although not shown, the inlet part of the device 10
14 (the space in which the carrier box 12 is fitted) is covered with an air curtain to block entry of contaminants such as dust.

The carrier box 12 includes a main body portion 18 having a handle 16,
A main body 18 including a door (first door) 20 that functions as a lid
In the vicinity of the edge portion 22 on the housing / extracting device 10 side (left side in FIG. 1), a fitting portion having a shape corresponding to the receiving inlet portion 14, that is, a step portion
24, are formed. The edge portion 22 and the step portion 24 are provided with sealing members 26 and 28, respectively. The seal member 26 may be provided on the surface of the first door 20 on the carrier box body 18 side (right side in FIG. 1), and the seal member 28 may be provided on the edge portion 30 (the step portion 24 of the accommodating and ejecting device 10). It may be provided at the opposite edges).

The storage and extraction device 10 includes a device main body 32, an arm 34, and a first
In the drawing, the lower chamber 36 below the arm 34, a door (second door) 38 that functions as a lid, and a connection chamber 40 that is an internal space of the apparatus main body 32 are roughly configured. The connection chamber 40 communicates with the switching valve 44 via the connection pipe 42. When the switching valve 44 is appropriately switched by a valve switching means (not shown in FIG. 1), the connection chamber 40 is selectively communicated with a vacuum source (not shown) or the atmosphere.

The arm 34 is provided with a seal member 46,
Electromagnets 48, 48 are embedded. And this electromagnet 4
8 and 48 are supplied with current from a DC power supply 50.

The lower chamber 36 below the arm 34 is composed of a flexible member 52 such as a diaphragm and a bottom plate 54. Here, the flexible member 52 is fixed to the apparatus main body 32 in a replaceable manner. Further, the arm 34 is welded to the bottom plate 54 (reference numeral
It is fixed by 56).

The bottom plate 54 is connected via a transmission member 58 and a transmission rod 60 to a drive motor 62 that is an arm drive means. The transmission member 58 and the transmission rod 60 are for transmitting the rotation of the drive motor 62 to the arm 34 while converting the rotation. A well-known technique can be diverted to the structure as it is, and therefore, illustration and description thereof are omitted.

A seal member is provided at the boundary between the device body 32 and the second door 38.
64 is provided, and further a mechanism (not shown) for opening and closing the first door 38 is provided.

Although not shown in FIG.
A central control unit that enables automatic operation in 10 is provided, and various sensors are also arranged. Second
For that purpose, the figure shows the outline of the circuit for automatic operation or automatic control.

In FIG. 2, a central control unit is designated by reference numeral 70, and a fitting detection sensor 72 for detecting whether or not the carrier box 12 is fitted in the inlet / outlet portion 14 of the accommodating / takeout device 10 is shown in the unit 70. And the output of the connection chamber pressure detection sensor 74 that detects the pressure of the connection chamber 40 are input. On the other hand, the central control unit 70 includes a motor 62 as an arm driving means, a DC power source 50 for electromagnets, a valve switching means 76 for switching the valve 44, and a second door opening / closing means 78 for opening / closing the second door 38. Then, the control signal is output.

In FIG. 2, transmission paths of output signals from various sensors and control signals of the central control unit 70 are shown by arrows. Although not shown in FIG. 2, the first door 20
A contact sensor for detecting whether or not the arm 34 is in contact with the arm 34 and a second door opening / closing sensor for detecting opening / closing of the second door 34 may be provided.

Next, with reference to the flow charts of FIG. 1 and FIG. 3, an aspect of taking out the contents of the carrier box 12 or accommodating the contents according to the present invention will be described.

First, the carrier box 12 is fitted into the receiving port portion 14 of the accommodating and ejecting device 10 through an air curtain (not shown) (step S1). Whether or not this fitting is completed is detected by the fitting detection sensor 72 shown in FIG.

If the fitting is done correctly (Yes in step S1),
The motor 62 is driven to bring the arm 34 into contact with the first door 20, and a current is passed from the DC power supply 50 to the electromagnets 48, 48 to cause the first door 20 to move.
The 20 is attached to the arm 34 (step S2). And
The valve 44 is connected to the vacuum source side by the valve switching means 76 (FIG. 2) (step S3), and so-called vacuuming is performed until the connection chamber 40 reaches a predetermined vacuum pressure (step S4). Step S4
In, whether or not the connection chamber 40 has a predetermined vacuum pressure,
It may be measured by the connection chamber pressure sensor 74 (Fig. 2).

It is also possible to carry out step S2 after step S4.

When the connection chamber 40 reaches a predetermined vacuum pressure (Step S4 is Ye
s), there is no pressure difference between the inside of the carrier box 12 and the connection chamber 40, and the first door 20 can be opened. In this state, the motor 62 is driven again to move or retreat the arm 34 in the direction of the arrow M1 and then move or descend in the direction of the arrow D (step S5), and the arm 34 is housed in the lower chamber 36. Here, since the first door 20 is attracted to the arm 34, the first door 20
20 will also be accommodated in the lower chamber 36.

At this stage, both the connection chamber 40 and the inside of the carrier box 12 are in a vacuum state, and a pressure difference exists between the outside of the second door 38 (inside the clean room C). Therefore, it is difficult to open the second door 38. Therefore, in order to eliminate the pressure difference, the valve switching means 76 (FIG. 2) connects the valve 44 to the atmosphere side (step S6), and the connection chamber 40
The vacuum is broken until the pressure reaches a predetermined pressure (atmospheric pressure) (step S7). In step S7, the connection chamber pressure sensor 74 (FIG. 2) also measures whether or not the connection chamber 40 has reached a predetermined pressure.

When the pressure difference disappears, the second door opening / closing means 78 (FIG. 2) opens the second door 38 (step S8), and the wafer is taken out or accommodated through the opening by means not shown. (Step S9).

It is preferable that the second door 38 be removed as it is like the first door 20. This is because if a double door opening or other opening / closing method by rotation is adopted, dust or the like is generated in the sliding portion of the rotation shaft, which adversely affects the yield of semiconductor products. In other words, when the opening / closing method based on the rotation such as the double door opening is adopted, the dustproof mechanism requires a special device.

Next, with reference to mainly the flowcharts of FIGS. 1 and 4, the manner in which the carrier box 12 is unfitted from the inlet / outlet portion 14 of the accommodating / extracting device 10 will be described.

When the taking out or accommodation of the wafer is completed (Yes in step S10), the second door 38 is closed by the second door opening / closing means 78 (FIG. 2) (step S11). Here, in order to prevent contaminants from being mixed into the carrier box 12 in which the taking out or housing of the wafer is completed, it is necessary to evacuate the carrier box. Therefore, the valve 44 is connected to the vacuum source side by the valve switching means 76 (FIG. 2) (step S12), and the inside of the connection chamber 40 and the carrier box 12 is evacuated to a predetermined vacuum pressure (step S13). ). In step S13, it is measured by the connection chamber pressure sensor 74 (FIG. 2) whether or not the predetermined vacuum pressure is reached.

Next, the motor 62 is driven to move or raise the first door 20 and the arm 34 housed in the lower chamber 36 in the direction of arrow U. Then, until the first door 20 contacts the edge portion 22 of the main body portion 18 of the carrier box 12, the first door 20 and the arm 34.
Move or move forward in the direction of arrow M2 (step S1
Four).

At this stage, the connection chamber 40 and the inside of the carrier box 12 are airtightly separated by the seal 26. And valve
When 44 is switched to the atmosphere side (step S15) and the connection chamber 40 is set to the atmospheric pressure (step S16 is Yes), the first door 20 is closed due to the differential pressure.

Next, the current supply from the DC power source to the electromagnets 48, 48 is stopped to separate the first door 20 from the arm 34, and the motor 62 is driven to retract the arm 34 in the direction of arrow M1 (step S17). . In this state, there is no mechanical connection between the carrier box 12 and the inlet / outlet portion 14 of the accommodating / extracting device 10, so that the fitted state of the carrier box 12 is released (step S18).

When the inside of the carrier box 12 is filled with an inert gas such as N ₂ without being evacuated, the above steps S12, S13,
S15 and S16 are unnecessary. Instead, it is necessary to hold the first door 20 in contact with the edge 22 of the carrier box 12 by a stopper (not shown).

The illustrated embodiment is merely an example and does not limit the scope of the present invention. For example, the contact sensor detects whether or not the first door 20 and the arm 34 are in contact with each other,
The opening / closing of the second door 34 is detected by the second door opening / closing sensor, and the outputs of these sensors are input to the central control unit 70 to make the fourth
The work shown in the flowchart of the figure can be performed.

In addition, as shown in FIG.
Tapered surfaces 14B and 24B may be formed on 14A and fitting portion 24A, respectively, and seal member 28A may be provided on tapered surface 24B. Although not shown, the embodiment of FIG.
A mechanism for preventing wear and damage of the seal material 28A due to sliding of 14B and 24B and dust generation accompanying it is configured.

 In addition, it will be added that various modifications are possible.

[Effects of the Invention] The effects of the present invention are listed below.

(1) It is not necessary to provide a valve on the carrier box itself.

(2) The weight of the carrier box is reduced.

(3) Since it is not necessary to connect and disconnect the valve and the vacuum source side system each time, the labor of accommodating and unloading the contents such as wafers is reduced.

(4) Vacuuming and breaking of the carrier box can be performed reliably and easily.

(5) Automatic control is possible.

(6) By devising the installation position of the seal member, the possibility of dust generation is greatly reduced and the life of the seal is improved.

(7) It is easy to implement because only the storage and extraction device is installed inside the existing clean room or on the wall thereof.

(8) Dust generation when opening and closing the door is suppressed.

[Brief description of drawings]

FIG. 1 is a sectional front view of an embodiment of the present invention, FIG. 2 is a block diagram showing automatic control, and FIGS. 3 and 4 are flowcharts of the operation of the embodiment of FIGS. 1 and 2, respectively. FIG. 5, FIG. 5 is a sectional front view of a conventional technique, FIG. 6 is a perspective view of another conventional technique, and FIG. 7 is a partially enlarged view showing an example of the shape of the fitting portion of the carrier box of the present invention. . 1, 12 ...... Carrier box, 10 …… Accommodating and ejecting device, 20
...... First door, 22 ...... edge, 24 ...... step, 26, 28, 46 ...
… Seal member, 34 …… arm, 38 …… second door, 40 ……
Connection chamber, 44 ... Valve

Continuation of the front page (51) Int.Cl. ⁶ Identification number Office reference number FI technical display location H01L 21/68 T

Claims (3)

[Claims] 1. A method of accommodating and extracting a content in a carrier box, wherein a content is stored in or extracted from a carrier box having a vacuum inside, and a carrier box having a first door is received by a storage box. A step of fitting the first chamber to the first door side, a step of bringing a connection chamber provided inside the accommodating and extracting device into communication with a vacuum source and the atmosphere through a valve into a vacuum state, and the connection chamber. Adsorbing the arm of the accommodating and ejecting device provided on the first door to the first door, moving the arm together with the first door of the carrier box, breaking the vacuum state of the connection chamber, and accommodating Opening the second door forming a part of the connection chamber of the take-out device to store the contents in the carrier box or to take out the contents, the contents of the carrier box Accommodate take-out method of. 2. A carrier box contents accommodating / discharging device for accommodating contents in a carrier box whose interior is in a vacuum state or for ejecting contents, wherein a carrier box having a first door is provided from the first door side. A receiving part for fitting and holding it, a connecting chamber communicating with a vacuum source and the atmosphere through a valve, an arm provided in the connecting chamber for contacting and adsorbing the first door, A suction means provided inside the arm, a lower chamber accommodating the first door and the arm, a driving means for driving the arm, and a second door forming a part of the connection chamber, And a device for storing and extracting the contents of a carrier box, comprising: 3. The carrier box used in the accommodating / discharging device according to claim 2, wherein a portion of the side wall of the main body portion near the first door side edge portion has a shape corresponding to the inlet / outlet portion of the accommodating / discharging device. A mounting member is formed and is provided at a boundary between the first door and the first door side edge of the side wall of the main body, and a seal member for making the boundary airtight; and the receiving port and the fitting part. A carrier box provided at a boundary for sealing the boundary.