JP7111146B2 - In-container cleaning device - Google Patents

Description

The present invention relates to an in-container cleaning apparatus, and more particularly, to an in-container cleaning apparatus and cleaning method for cleaning the inside of a wafer transfer container.

In a semiconductor manufacturing process, a container called a FOUP or the like is used to transfer wafers between processing apparatuses.

Here, the environment in the container in which the wafers are housed is preferably maintained in an inert state and cleanliness higher than a predetermined state in order to protect the wafer surfaces from oxidation and contamination. As a method for improving the inert state and cleanliness of the gas in the transport container, there is a load port device that introduces cleaning gas into the transport container through the bottom hole formed in the bottom surface of the transport container and the main opening of the container. and an EFEM including this has been proposed (see Patent Document 1).

JP-A-2003-45933

However, in the conventional method of cleaning the inside of the transfer container using the load port device included in the EFEM, the inside of the transfer container is cleaned after the transfer container is placed on the load port device and before the start of unloading of the wafers. It will be. As a result, there may be a problem that the removal of wafers from the container cannot be started until the cleaning of the inside of the container is completed. there is

SUMMARY OF THE INVENTION It is an object of the present invention to provide an in-container cleaning apparatus and a cleaning method for cleaning a wafer transfer container without lowering the operation rate of processing equipment in a semiconductor factory.

In order to achieve the above object, the present invention provides an in-container cleaning apparatus for cleaning the inside of a wafer transfer container having a container main opening from which wafers can be taken out, comprising:
a mounting section for mounting the wafer transport container;
a cleaning chamber comprising a device opening that connects to the container main opening;
an opening/closing mechanism that opens and closes a lid that closes the container main opening and a door that closes the apparatus opening, and communicates the inside of the wafer transfer container with the cleaning chamber;
a gas introducing means capable of introducing a cleaning gas into the wafer transfer container;
a gas detection unit that detects at least one of gas components and gas cleanliness in the wafer transfer container;
a control unit that controls introduction of the cleaning gas into the wafer transfer container using the output of the gas detection unit.

The apparatus for cleaning the interior of the container according to the present invention is installed separately from the EFEM and the processing chamber in the semiconductor factory. It is possible. By moving the wafer transport container cleaned by the container interior cleaning device to a load port device attached to the processing equipment, the load port device cleans the wafers housed in the transport container after movement into a mini-environment or a mini-environment. It is possible to quickly move the wafer to the processing chamber, thereby improving the operating rate of the processing apparatus. In addition, since there is no need to install a wafer transfer device or the like in the cleaning chamber of the container interior cleaning apparatus, there are fewer sources of particle generation, and the volume of the cleaning chamber is smaller than that of a mini-environment or the like. Therefore, it is possible to effectively clean the inside of the wafer transfer container.

Further, since the apparatus for cleaning the interior of the container according to the present invention has the gas detection section and the control section for controlling the introduction of the cleaning gas using the output of the gas detection section, it is possible to reliably clean the inside of the wafer transfer container. It can protect the wafer surface from oxidation and contamination. In addition, by detecting the components of the gas inside the wafer transport container and the degree of cleanliness of the gas, it is possible to shorten the time required for cleaning, making cleaning more efficient and economical than before. Realize

Further, for example, the mounting section includes a bottom nozzle that communicates on one side with a bottom hole formed in the bottom surface of the wafer transport container, and a pipe that communicates with the bottom nozzle on the other side of the bottom nozzle. and
The gas detection section is provided in the bottom nozzle or the piping section, and detects the gas that has flowed out from the inside of the wafer transfer container through the bottom hole to detect the components of the gas in the wafer transfer container. and at least one of cleanliness of the gas.

Since such a cleaning apparatus detects the gas in the wafer transfer container through the bottom hole of the container, even when the lid of the wafer transfer container and the door of the cleaning chamber are closed, the wafer transfer container can be detected. It is possible to detect the composition of the gas inside and the cleanliness of the gas. Therefore, according to such a cleaning apparatus, for example, the atmosphere in the cleaning chamber can be adjusted according to the detected gas component, and the already cleaned wafer transfer container can be cleaned without opening the lid. By terminating the treatment in the cleaning device, more efficient and economical cleaning than in the past can be achieved.

Further, for example, the cleaning apparatus according to the present invention may have an acceleration detection section for detecting acceleration of the wafer transport container,
The controller may further use the output of the acceleration detector to control introduction of the cleaning gas into the wafer transfer container.

Such a container interior cleaning apparatus has an acceleration detection unit for detecting an acceleration related to an increase or decrease in the number of particles in the wafer transfer container. It can be made into a state of high cleanliness with less. Further, in such a container cleaning apparatus, if for some reason the container cleaning apparatus is not properly placed on the mounting table, the acceleration detecting section detects an acceleration larger than usual when gas is introduced. Since it is detected, it is possible to easily detect a state in which the container cleaning device is not correctly placed.

Further, for example, the acceleration detection section may be provided on a wafer transfer container installation surface of the mounting section.

By providing the acceleration detector on the wafer transfer container installation surface, it is possible to directly and accurately measure the acceleration of the wafer transfer container.

Further, for example, the gas introduction means may have an indoor gas discharge section provided inside the cleaning chamber and capable of switching between clean dry air and an inert gas as the cleaning gas and discharging the cleaning gas. .

Such an apparatus for purifying the inside of a container has an indoor gas discharge section capable of switching between clean dry air and inert gas, so that the state of the purifying chamber can be changed between the clean dry air filling state and the inert gas filling state. It is possible to switch to Here, in cleaning the inside of the wafer transfer container, it is necessary to use an inert gas to prevent the surface of the wafer from being oxidized. Therefore, it is conceivable to always clean the inside of the cleaning chamber with an inert gas, but in this case, there is a risk that the operator will mistakenly inhale the inert gas, and there is a risk that the cost will increase. Therefore, these problems can be solved by filling the cleaning chamber with clean dry air except when the inside of the wafer transfer container is being cleaned. In other words, after the cleaning of the wafer transfer container is completed, the cleaning chamber is filled with clean dry air, thereby effectively preventing the operator from inhaling inert gas by mistake. Excellent for In addition, since it is possible to prevent the problem of the inert gas flowing out of the device, it is possible to suppress the consumption of the inert gas.

Further, for example, the container interior cleaning apparatus according to the present invention may have an external detection unit that detects at least one of the components of the gas outside the wafer transfer container and the cleanliness of the gas,
The controller may further use the output of the external detector to control the introduction of the cleaning gas into the wafer transfer container.

The process of cleaning the inside of the wafer transfer container is preferably carried out in a state in which the inside of the wafer transfer container and the cleaning chamber communicating therewith are isolated from the external environment. Influx can also occur. Therefore, by using the output from the external detection unit that detects the components of the gas outside the wafer transfer container and the cleanliness of the gas, such a container interior cleaning apparatus can clean the inside of the wafer transfer container under more appropriate conditions. A cleaning gas can be introduced into the

Further, for example, the container interior cleaning apparatus according to the present invention may have a storage unit that stores the output of the gas detection unit,
The control section may use the past output of the gas detection section stored in the storage section to change a control condition regarding the introduction of the cleaning gas into the wafer transfer container.

Such an in-container cleaning apparatus refers to the past output stored in the storage unit and changes the control conditions for introducing the cleaning gas into the wafer transfer container, thereby making the cleaning process more efficient and economical. The inside of the wafer carrier can be cleaned.

FIG. 1 is a schematic diagram showing an installation state in a semiconductor factory of an in-container cleaning apparatus according to an embodiment of the present invention. FIG. 2 is a schematic cross-sectional view of an in-container cleaning apparatus according to an embodiment of the present invention. 3A and 3B are schematic cross-sectional views showing the first and second stages of the cleaning method by the in-container cleaning apparatus shown in FIG. 4A and 4B are schematic cross-sectional views showing the third and fourth stages of the cleaning method by the in-container cleaning apparatus shown in FIG. 5A and 5B are schematic cross-sectional views showing the fifth and sixth steps of the cleaning method by the in-container cleaning apparatus shown in FIG. FIG. 6 is a flow chart showing an example of a cleaning method by the in-container cleaning apparatus shown in FIG. FIG. 7 is a schematic cross-sectional view of an in-container cleaning apparatus according to a second embodiment of the present invention.

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, the present invention will be described based on embodiments shown in the drawings.
FIG. 1 is a schematic diagram showing an arrangement state in a semiconductor factory of an in-container cleaning apparatus 10 according to an embodiment of the present invention. As shown in FIG. 1, the in-container cleaning system 10 is located in a semiconductor factory adjacent to a processing system 50 with an associated load port system 51 . The in-container cleaning apparatus 10 is installed separately from the processing apparatus 50 having the EFEM and the processing chamber in the semiconductor factory.

The container interior cleaning device 10 is a device separated from other processing chambers for cleaning the inside of a FOUP 2 as a wafer transfer container. Therefore, in the cleaning chamber of the container interior cleaning apparatus 10, there is no transfer robot or the like for taking out the wafer 1 from the FOUP 2, and there are no other mini-environments or doors leading to the processing chamber. not formed (see FIG. 2). As shown in FIG. 1, in the container interior cleaning apparatus 10, the mounting portion 14 for mounting the FOUP 2 and the like have the same size as the load port device 51 and the like attached to the processing chamber, but the wafer 1 from the FOUP 2 and processing the removed wafer 1, the size of the processing apparatus 50 is smaller than that of the processing apparatus 50. FIG.

FIG. 2 is a schematic cross-sectional view of the in-container cleaning apparatus 10, showing a state in which the FOUP 2 is placed on the placing portion 14. As shown in FIG. The FOUP 2 to be cleaned by the container interior cleaning apparatus 10 has a container main opening 2b from which the wafer 1 can be taken out. The container main opening 2b is sealed with a lid 4, and in the FOUP 2, a plurality of wafers 1 before or after being processed by the processing apparatus 50 are hermetically stored.

The bottom surface 2e of the hoop 2 is formed with a first bottom hole 2ea and a second bottom hole 2eb as bottom holes. The sizes of the first bottom hole 2ea and the second bottom hole 2eb are such that the gas in the FOUP 2 in which the wafer 1 is housed can flow out, or the first bottom nozzle 21a and the second bottom nozzle 21b, which will be described later, can flow out. Although the size is not particularly limited as long as it allows gas to flow into the hoop 2 through the hole, it is, for example, about φ10 to 30 mm, which is sufficiently small compared to the diameter of the wafer 1 .

The first bottom hole 2ea and the second bottom hole 2eb are provided with valves (not shown) so that the first bottom nozzle 21a and the second bottom nozzle 21b are connected to the first bottom hole 2ea and the second bottom hole 2eb. When leaving the hole 2eb, the valves of the first bottom hole 2ea and the second bottom hole 2eb are closed and the tightness inside the hoop 2 is maintained. The bottom surface 2e of the hoop 2 is provided with a contact portion with which the positioning pin 14c of the mounting portion 14 contacts, an engaging portion with which a hook for fixing the hoop 2 to the mounting portion 14 engages, and the like. However, the positions and shapes of the contact portion and the engaging portion are not particularly limited.

The object to be cleaned by the container interior cleaning device 10 of the present embodiment is the hoop 2 having the container main opening 2b formed on the side surface, but the container interior cleaning device according to the present invention is not limited to this. It may be one that cleans a wafer carrier other than the FOUP 2, such as Fosby (FOSB) or the like. Since the wafer transfer container conforming to the SEMI standard such as the FOUP 2 and Phosby has standardized positions and shapes of the container main opening 2b, cleaning inside the container is performed through the container main opening 2b. Apparatus 10 can be widely applied to wafer carriers conforming to SEMI standards.

As shown in FIG. 2, the apparatus for cleaning the inside of a container 10 includes a mounting portion 14 on which the FOUP 2 is placed, a cleaning chamber 11, and an opening/closing mechanism 15 for communicating the inside of the FOUP 2 with the cleaning chamber 11. , an indoor gas discharge unit 16 as gas introduction means capable of introducing cleaning gas into the hoop 2 , and a gas detection unit 30 for detecting the cleanliness of the gas in the hoop 2 . The in-container cleaning apparatus 10 also includes a control unit 20 for controlling introduction of cleaning gas into the hoop 2, a first bottom nozzle, an outlet opening/closing mechanism 19, and the like.

The mounting portion 14 is positioned below the FOUP 2 and includes a fixed table 14a, a slide table 14b that slides on the fixed table 14a, a first bottom nozzle 21a, a second bottom nozzle 21b, and a second bottom nozzle 21b. It has the 1st piping part 22a, the 2nd piping part 22b, and the 3rd piping part 22c. A gas detector 30 is provided at the end of the first pipe portion 22a and the second pipe portion 22b.

As shown in FIGS. 3(a) and 3(b), the slide table 14b moves with the hoop 2 placed thereon to connect the container main opening 2b of the hoop 2 to the apparatus opening 11aa of the cleaning chamber 11. do.

The first bottom nozzle 21a and the second bottom nozzle 21b are provided so as to protrude upward from the upper surface of the slide table 14b. As shown in FIG. 2, the upper ends of the first bottom nozzle 21a and the second bottom nozzle 21b contact the bottom surface 2e of the FOUP 2 fixed to the slide table 14b. The first bottom nozzle 21a has a cylindrical shape without a bottom, and can communicate on one side with a first bottom hole 2ea formed in the bottom surface 2e of the hoop 2, and communicate with the first pipe portion 22a on the other side. do. Similarly to the first bottom nozzle 21a, the second bottom nozzle 21b also has a bottomless cylindrical shape, and can communicate with the second bottom hole 2eb formed in the bottom surface 2e of the hoop 2 on one side. and communicates with the second pipe portion 22b on the other side.

The gas detection section 30 is provided in the piping section 22 which is composed of the first piping section 22a, the second piping section 22b, and the third piping section 22c. As shown in FIG. 2, the gas detection unit 30 is provided at the connecting portion of the pipe portion 22 to which the first to third pipe portions 22a to 22c are connected. Not limited.

The gas detection unit 30 detects at least one of the components of the gas flowing out of the FOUP 2 and the cleanliness of the gas (amount of particles contained in the gas). As the gas detection unit 30, it is preferable to detect the amount of gas components or particles in the gas that may affect the contamination of the wafers 1 housed inside the FOUP 2. For example, an oxygen concentration meter, moisture (water vapor) concentration meter, nitrogen concentration meter, particle counter, etc., but are not particularly limited.

The third pipe portion 22c constitutes a channel for discharging the gas detected by the gas detection portion 30 to the outside. The first to third pipe portions 22a to 22c are connected to each other at a connection portion where the gas detection portion 30 is installed, and the first pipe portion 22a connects the first bottom nozzle 21a and the connection portion. , the second pipe portion 22b connects the second bottom nozzle 21b and the connecting portion.

The gas detection unit 30 communicates the first pipe part 22a and the second pipe part 22b to return the outflowing gas to the hoop 2, and detects at least one of the first pipe part 22a and the second pipe part 22b. It may have a switching valve and a valve control means for controlling the switching valve, which is communicated with the pipe portion 22c to switch the state of discharging the outflow gas. For example, if the gas detection unit 30 is an oxygen concentration meter, the gas detection unit 30 detects that the oxygen concentration of the gas flowing out from the inside of the hoop 2 is smaller than a predetermined value. , and the gas that has flowed out from the interior of the hoop 2 can be returned to the interior of the hoop 2 again via the second pipe portion 22b. On the contrary, when the oxygen concentration of the gas flowing out from the inside of the hoop 2 is equal to or higher than the predetermined value, the gas detection unit 30 connects the first pipe part 22a and the third pipe part 22c, The gas that has flowed out from the inside of the hoop 2 can be discharged to the outside without returning to the inside of the hoop 2.

The cleaning chamber 11 is provided so as to face the FOUP 2 fixed to the slide table 14b of the mounting section 14, and has a substantially rectangular parallelepiped shape. A device opening 11aa connected to the container main opening 2b of the FOUP 2 is provided on the front wall portion 11a of the cleaning chamber 11 on the mounting portion 14 side. A device opening 11aa of the front wall portion 11a is provided with a door 13 for closing the device opening 11aa. By closing the device opening 11aa with the door 13, the cleaning chamber 11 is shielded from the external environment. there is

The cleaning chamber 11 is provided with an opening/closing mechanism 15 that opens and closes the cover 4 of the FOUP 2 and the door 13 that closes the opening 11aa of the device, thereby allowing the FOUP 2 and the cleaning chamber 11 to communicate with each other. The opening/closing mechanism 15 opens the container main opening 2b and the device opening 11aa by moving the door 13 and the lid 4 engaged with the door 13 into the cleaning chamber 11 . The opening/closing mechanism 15 has, for example, an arm connected to the door 13 and a motor that translates or rotates the door 13 to which the arm is connected, but the specific configuration of the opening/closing mechanism 15 is not particularly limited.

Since it is not necessary to take out the wafer 1 from the FOUP 2 in the container interior cleaning apparatus 10 , the moving distance of the lid 4 by the opening/closing mechanism 15 may be shorter than the opening length of the container main opening 2 b of the FOUP 2 . This is because the opening degree of the container main opening 2b is sufficient as long as the inert gas can be introduced into the hoop 2 . Further, the container interior cleaning apparatus 10 has a rear wall portion 11c facing the front wall portion 11a in which the apparatus opening 11aa is formed. diameter or less. By reducing the distance from the device opening 11aa to the rear wall portion 11c, the volume of the cleaning chamber 11 can be reduced and the interior of the hoop 2 can be efficiently cleaned. Further, the cleaning chamber 11 does not need to have a volume through which the wafer 1 can pass, unlike a mini-environment or the like connected by the load port device 51 or the like. If the lid 4 does not move in parallel, the moving distance of the lid 4 is the center-of-gravity moving distance.

The in-vessel cleaning apparatus 10 has, as the indoor gas discharge section 16, two gas discharge means, a first gas discharge means 16a and a second gas discharge means 16b. Both the first gas release means 16 a and the second gas release means 16 b are provided inside the cleaning chamber 11 .

The first gas discharge means 16a has a discharge port arranged in the upper part of the cleaning chamber 11 (in this embodiment, the upper surface wall portion 11d of the cleaning chamber 11), and the gas is emitted downward from the upper side of the cleaning chamber 11. Release gas. The first gas discharging means 16a can switch between clean dry air (CDA) and inert gas to discharge. Clean dry air and inert gas are supplied to the first gas discharge means 16a through a gas pipe (not shown). The control unit 20 controls the release and stop of the gas by the first gas release means 16a and the switching between the clean dry air and the inert gas. Here, clean dry air means air purified by removing moisture and particles from air in a general environment.

The second gas discharge means 16b has a discharge port arranged in the cleaning chamber 11 and discharges the inert gas toward the apparatus opening 11aa. The discharge port of the second gas discharge means 16b is arranged in the side wall portion 11b which is perpendicular to the top wall portion 11d and the front wall portion 11a of the cleaning chamber 11, the open door 13 and the front wall portion. This is preferable from the viewpoint of feeding the cleaning gas into the hoop 2 through the gap with 11a. In addition, the outlet of the second gas discharge means 16b may be divided into two side wall portions 11b facing each other, and this makes it possible to uniformly feed the inert gas into the hoop 2. . The inert gas released by the second gas release means 16b is supplied to the second gas release means 16b through a gas pipe portion (not shown) in the same manner as the first gas release means 16a.

Nitrogen gas and argon gas are conceivable as the inert gas discharged by the first and second gas discharge means 16a and 16b, but the components of the inert gas are not particularly limited.

In addition, the indoor gas discharge unit 16 has two gas discharge means 16a and 16b that differ in arrangement and the cleaning gas that can be discharged, but the indoor gas discharge unit 16 is not limited to this, and only one gas discharge means , or three or more gas discharge means having different arrangements and different cleaning gases.

In the embodiment described later, the first gas discharge part 16a is mainly used to change the composition (atmosphere) of the gas inside the cleaning chamber 11, and the function of introducing the cleaning gas into the hoop 2 is , mainly by the second gas release means 16b. However, the indoor gas discharge section 16 is not limited to this. For example, the indoor gas discharge section 16 may have only the first gas discharge means 16a, and the first gas discharge means 16a may It may serve both the function of changing the composition of the gas inside 11 and the function of introducing cleaning gas into the hoop 2 . In another embodiment, the indoor gas discharge section 16 includes a first gas discharge means for discharging CDA having a discharge port arranged on the upper surface wall portion 11d and an inert gas discharge means arranged on the side wall portion 11b. and a second gas releasing means 16b for releasing a gas, by switching the gas releasing means for releasing cleaning gas between the two gas releasing means, the CDA and the inert gas. can be switched and released.

The bottom wall portion 11e of the cleaning chamber 11 is provided with an outlet 18 through which clean dry air and inert gas released from the first gas releasing means 16a and the second gas releasing means 16b can be discharged from the cleaning chamber 11. is formed. The cleaning chamber 11 also has an outlet opening/closing mechanism 19 that opens and closes the outlet 18, and the operation of the outlet opening/closing mechanism 19 is controlled by a control unit 20, which will be described later.

The control unit 20 is provided outside the cleaning chamber 11, and has computing means such as a microprocessor, a storage unit 20a for storing the output of the gas detection unit 30, and the like. The control unit 20 receives an output from the gas detection unit 30 regarding the components of the gas in the FOUP 2 and the detected values of cleanliness. In addition, the control unit 20 sends signals to the driving unit that drives the slide table 14b, the first bottom nozzle 21a, and the second bottom nozzle 21b, the opening/closing mechanism 15, the outlet opening/closing mechanism 19, the gas detection unit 30, and the like. By inputting and outputting , the operation of each part is controlled, and the introduction of the cleaning gas into the hoop 2 by the in-container cleaning device 10 is controlled.

The control unit 20 can use the output of the gas detection unit 30 when controlling the operation of each part of the in-container cleaning apparatus 10 . For example, according to the output value of the gas detection unit 30, the control unit 20 introduces the cleaning gas into the target FOUP 2 and then causes the FOUP 2 to be transported to another device, or causes the FOUP 2 to be fed with the cleaning gas. It is possible to choose whether the hoop 2 is transported to another device without introducing the . Further, for example, the control unit 20 can change the amount of gas released, the release speed, the release time, etc. when introducing the cleaning gas into the target FOUP 2 according to the output of the gas detection unit 30. . In addition, for example, the control unit 20 uses the output of the gas detection unit 30 to switch the release gas in the first gas release means 16a and to start gas release in the first and second gas release means 16a and 16b. In addition, it is possible to control the discharge stop, the opening amount of the discharge port 18 by the discharge port opening/closing mechanism 19, and the like.

3 to 5 and a flow chart shown in FIG. 6, an example of a method for cleaning the hoop 2 using the apparatus 10 for cleaning the inside of the container shown in FIG. 2 will be described in detail. to explain. 3 to 5 do not show a part of the configuration included in the in-container cleaning apparatus 10 shown in FIG. 2 for convenience of explanation.

FIG. 3(a) represents the first stage of the cleaning method. In the first stage of the cleaning method, the hoop installation process (step S001) shown in FIG. 6 and the first detection process (step S002) by the gas detection unit 30 are performed. In the FOUP installation process (step S001), the FOUP 2 is transported and installed on the platform 14 via OHT (overhead transport) or the like in the factory.

Next, in the first stage of the cleaning method, a first detection process (step S002) is performed by the gas detector 30. FIG. More specifically, first and second bottom nozzles 21a and 21b shown in FIG. It flows into the piping section 22 . A gas detection unit 30 provided in the piping unit 22 detects the components and cleanliness of the gas that has flowed out from the FOUP 2 and outputs them to the control unit 20 . The control unit 20 compares the gas component and the particle amount detected by the gas detection unit 30 with a predetermined threshold value. At this time, the storage unit 20 a in the control unit 20 stores the output of the gas detection unit 30 .

If the control unit 20 determines that the interior of the FOUP 2 is already clean at the stage of step S002, the process proceeds to step S010, where the FOUP 2 is cleaned by another device without introducing the cleaning gas into the FOUP 2. be transported to On the other hand, when the control unit 20 determines that the FOUP 2 is not as clean as the predetermined state, the process proceeds to step S003 and the subsequent steps. The criteria for judging whether the inside of the hoop 2 is clean (or not clean) are not particularly limited as long as they can be judged using the output of the gas detection unit 30. For example, If the amount of oxygen, water vapor, particles, or the like that is introduced into the hoop 2 is below a predetermined value, it can be determined that the inside of the hoop 2 is clean.

In the first stage of the cleaning method, as shown in FIG. 3(a), the inside of the cleaning chamber 11 is filled with clean dry air. That is, clean dry air is discharged from the first gas discharge means 16a in the container interior cleaning apparatus 10, and the door 13 is closed to shield the cleaning chamber 11 from the external environment. Clean dry air is installed. Further, by keeping the discharge port 18 open, a flow of clean dry air is formed from the top to the bottom of the cleaning chamber 11, so that the inside of the cleaning chamber 11 can be kept in a cleaner state. .

FIG. 3(b) represents the second stage of the cleaning method. In the second stage of the cleaning method, as a preparatory process for cleaning the interior of the FOUP 2, the gas switching/table moving process (step S003) shown in FIG.

In the gas switching/table moving process shown in step S003, the control unit 20 first switches the gas released by the first gas releasing means 16a from clean dry air to inert gas, and supplies the inert gas to the cleaning chamber 11. Introduce. By introducing such an inert gas, the clean dry air filled in the cleaning chamber 11 in the first stage shown in FIG. is filled with inert gas.

Further, in the gas switching/table moving process (step S003), the control unit 20 moves the slide table 14b of the mounting unit 14 toward the cleaning chamber 11 so that the apparatus opening 11aa of the cleaning chamber 11 is moved to the FOUP 2. to the container main opening 2b. Even if the slide table 14b is moved, the communication between the first and second bottom nozzles 21a, 21b and the first and second bottom holes 2ea, 2eb is maintained.

FIG. 4(a) represents the third stage of the cleaning method. In the third stage of the cleaning method, door opening processing (step S004), gas release processing (step S005), and second detection processing (step S006) shown in FIG. 6 are performed.

As shown in FIG. 4A, in the door opening process (step S004), the control unit 20 operates the opening/closing mechanism 15 so as to open the lid 4 that closes the container main opening 2b and the door 13 that closes the device opening 11aa. By driving, the inside of the hoop 2 and the cleaning chamber 11 are communicated. Furthermore, in the gas release process (step S005), the control unit 20 releases the inert gas from the second gas release means 16b and introduces the inert gas into the hoop 2 communicating with the cleaning chamber 11. FIG. The second gas releasing means 16b can efficiently clean the inside of the hoop 2 by releasing the inert gas toward the device opening 11aa and the hoop 2 communicating through the device opening 11aa. The gas present in the hoop 2 before cleaning is discharged through the cleaning chamber 11 and through the outlet 18 . In the third stage of the cleaning method, part of the inert gas released by the first gas releasing means 16a is removed by using, for example, a rectifying plate or the lid 4 moved into the cleaning chamber 11. The direction of flow may be adjusted and introduced into the hoop 2 .

In the third stage of the cleaning method shown in FIG. 4(a), the control unit 20 performs the second detection process (step S006). Also in the third stage of the cleaning method, the first and second bottom nozzles 21a, 21b communicate with the first and second bottom holes 2ea, 2eb of the hoop 2, so that the gas inside the hoop 2 flows into the piping portion 22 . The gas detection unit 30 provided in the piping unit 22 detects the components and cleanliness of the gas flowing out from the FOUP 2 and outputs them to the control unit 20 in the same manner as in the first detection process of step S002. The control unit 20 compares the gas component and the particle amount detected by the gas detection unit 30 with a predetermined threshold value. At this time, the storage unit 20 a in the control unit 20 stores the output of the gas detection unit 30 .

If the control unit 20 determines that the inside of the FOUP 2 is clean at the time of the second detection process (step S006) after the gas introduction process (step S005), the process proceeds to the gas stop process of step S007. On the other hand, if the control unit 20 determines that the inside of the hoop 2 is not clean at the time of the second detection process (step S002), it continues the gas release process (step S005), and after a predetermined time, 2 detection processing (step S006) is performed. The criteria for judging that the inside of the hoop 2 is clean (or not clean) may be the same as the criteria for judging that the inside of the hoop 2 is clean (or not clean) in step S002, or may be different. may

FIG. 4(b) represents the fourth stage of the cleaning method. In the fourth stage of the cleaning method, gas stop processing (step S007) shown in FIG. 6 is performed. As shown in FIG. 4(b), in the gas stop processing of step S007, the release of the inert gas by the second gas release means 16b is stopped.

FIG. 5(a) represents the fifth stage of the cleaning method. In the fifth stage of the cleaning method, door closing processing (step S008) and gas switching/table moving processing (step S009) shown in FIG. 6 are performed. As shown in FIG. 5A, in the door closing process of step S008, the control unit 20 drives the opening/closing mechanism 15 so as to close the lid 4 closing the container main opening 2b and the door 13 closing the device opening 11aa. to separate the inside of the hoop 2 from the cleaning chamber 11 .

Next, in the gas switching/table moving process of step S009, the control unit 20 emits clean dry air from the first gas discharging means 16a and introduces the clean dry air into the cleaning chamber 11. FIG. More specifically, the control unit 20 shown in FIG. 2 detects that the door 13 and the lid 4 are closed and the inside of the hoop 2 is separated from the cleaning chamber 11, and then the first gas release means 16a is turned off. The clean dry air is introduced into the cleaning chamber 11 by switching the discharged gas from the inert gas to the clean dry air and discharging the clean dry air from the first gas discharging means 16a. By introducing the clean dry air, the inert gas filling the cleaning chamber 11 after the process of step S003 in FIG.

In addition, in the gas switching/table moving process of step S009, the control unit 20 moves the slide table 14b of the mounting unit 14 away from the cleaning chamber 11 so that the apparatus opening 11aa of the cleaning chamber 11 and the FOUP 2 are separated. The connection with the container main opening 2b is released. Further, the control unit 20 moves the slide table 14b to move the hoop 2 to the OHT delivery position as shown in FIG. 5(b).

FIG. 5(b) represents the sixth stage of the cleaning method. In the sixth stage of the cleaning method, the hoop transfer process (step S010) shown in FIG. 6 is performed. In the FOUP transport process of step S010, the FOUP 2 moved to the delivery position is transported by the OHT to the load port device 51 of the other processing device 50 at a predetermined timing. Thereafter, each time the FOUP 2 in the semiconductor factory is transported to the placement section 14, the above-described first to sixth steps (steps S001 to 010 in FIG. 6) are repeated.

After the hoop 2 is separated from the cleaning chamber 11 as shown in FIG. 5(b), the first gas releasing means 16a is kept closed until the next hoop 2 is placed in FIG. 3(a). Alternatively, clean dry air may be continuously discharged into the cleaning chamber 11. For example, after discharging the inert gas in the cleaning chamber 11 by discharging the clean dry air for a predetermined time, the gas is discharged. You can stop. It is preferable that the outlet opening/closing mechanism 19 shown in FIG.

According to the cleaning method as described above, after cleaning of the hoop 2 is completed, the cleaning chamber 11 is filled with clean dry air. It can be effectively prevented, and it is excellent from the viewpoint of safety of factory equipment. In addition, since the problem of the inert gas flowing out from the in-container cleaning apparatus 10 can be prevented, the consumption of the inert gas can also be suppressed.

In addition, by cleaning the inside of the FOUP 2 using the container interior cleaning device 10 installed separately from the load port device 51 attached to the processing apparatus 50, the load port device 51 attached to the processing chamber can be cleaned. It is possible to quickly take out the wafer 1 before processing without performing the hardening process, and to quickly move the FOUP 2 containing the wafer 1 after processing, thereby improving the operating rate of the processing apparatus 50. can. In addition, the stand-alone container interior cleaning apparatus 10 does not require installation of a transfer device or the like for the wafer 1 in the cleaning chamber 11, so there are few sources of particle generation. The inside of the hoop 2 can be effectively cleaned because the volume may be smaller than that of the ment or the like.

In addition, since the in-container cleaning apparatus 10 has the first gas releasing means 16a for changing the environment of the cleaning chamber 11 and the second gas releasing means 16b for sending cleaning gas into the hoop 2, the hoop 2 can be efficiently cleaned. Furthermore, since the container interior cleaning device 10 cleans the inside of the FOUP 2 through the container main opening 2b, which has a unified standard, for example, when multiple types of FOUPs 2 are used in a factory. Even if there is, it can be used without problems.

In addition, since the in-vessel cleaning apparatus 10 has the control unit 20 that controls the introduction of the cleaning gas using the output of the gas detection unit 30, the FOUP 2 can be reliably cleaned, and the wafer 1 can be protected from oxidation and contamination. In addition, by detecting the components of the gas inside the hoop 2 and the degree of cleanliness of the gas, it is possible to shorten the time required for cleaning. come true.

Further, in order to detect gas in the hoop 2 through the bottom holes 2ea and 2eb of the hoop 2, the in-container cleaning device 10 closes the main container opening 2b of the hoop 2 and the device opening 11aa of the cleaning chamber 11. Even in this state, it is possible to detect the components of the gas in the hoop 2 and the cleanliness of the gas. According to the in-container cleaning device 10, efficient and economical processing can be achieved by terminating the processing by the in-container cleaning device 10 without opening the lid 4 for the hoop 2 that has already been cleaned. come true.

Although the present invention has been described above with reference to the embodiments, it is needless to say that the present invention is not limited to these embodiments and includes various modifications. For example, as shown in FIGS. 4(a) and 4(b), the lid 4 and door 13 removed from the container main opening 2b of the hoop 2 or the apparatus opening 11aa of the cleaning chamber 11 by the opening/closing mechanism 15 are attached to the rear wall portion. Although it may be held obliquely with respect to 11c, it may be held parallel to the rear wall portion 11c.

Further, the cleaning method performed by the in-container cleaning apparatus 10 is not limited to performing the processes shown in steps S001 to S010 of FIG. is. For example, the control unit 20 may change the control conditions for introducing the cleaning gas into the FOUP 2 using past outputs of the gas detection unit 30 stored in the storage unit 20a. For example, the control unit 20 can change the threshold for determining that the FOUP 2 is clean in step S002 shown in FIG. 6 according to the post-cleaning output detected in step S006. If the cleanliness level detected in step S006 is higher than a predetermined value and the cleaning process in steps S004 to S008 is expected to improve the cleanliness level more than expected, the threshold value in step S002 is changed to a higher level of cleanliness. can. Conversely, if the cleanliness level detected in step S006 is lower than the predetermined value and the cleaning process in steps S004 to S008 is unlikely to improve the cleanliness level as expected, the threshold value in step S002 is set to a higher level of cleanliness. can be changed to the lower side.

As another example, the control unit 20 changes the threshold for judging that the FOUP 2 is clean in step S006 shown in FIG. 6 according to the past output detected in step S006. As a result, it is possible to prevent the gas introduction process in step S005 from continuing for a long time or from timing out.

In addition, in the apparatus for cleaning the inside of a container 10, the gas detection section 30 may be provided in the piping section 22 as shown in FIG. bottom nozzles 21a and 21b. Further, the gas detection unit 30 introduces the gas in the hoop 2 through a nozzle that communicates with the hole in the side surface or the top surface of the hoop 2 instead of the bottom surface 2e of the hoop 2, and detects the components of the gas in the hoop 2 and the amount of the gas. At least one of cleanliness may be detected. Furthermore, the detection sensor of the gas detection unit 30 may be provided inside the hoop 2, and the gas detection unit 30 may communicate the output of the detection sensor in the hoop 2 using wiring or transmission/reception means. good.

The bottom hole of the hoop 2 and the number of bottom nozzles communicating therewith are not particularly limited. may be provided for the purpose of

FIG. 7 is a schematic cross-sectional view of an in-container cleaning apparatus 110 according to the second embodiment. In the in-container cleaning apparatus 110, the first pipe portion 122a and the second pipe portion 122b are not connected, and the gas detection portion 30 and the discharge pump 146 are provided in the first pipe portion 122a. Although it differs from the in-container cleaning device 10 according to the first embodiment in that it has a detection unit 142, an external detection unit 143, and a second gas detection unit 144, the other points are the same as the in-container cleaning device 10 (FIG. 2). Therefore, regarding the in-container cleaning apparatus 110, only the differences from the in-container cleaning apparatus 10 will be described, and the same reference numerals will be given to the common points, and the description will be omitted.

The first pipe portion 122 a of the in-container cleaning device 110 is connected to the first bottom nozzle 21 a communicating with the first bottom hole 2 ea of the hoop 2 . In the first pipe section 122a, the gas detection section 30 is arranged closer to the first bottom nozzle 21a than the discharge pump 146 is. The discharge pump 146 can suck the gas inside the hoop 2 through the first bottom hole 2ea and the first bottom nozzle 21a. By operating the exhaust pump 146 , the controller 120 can reliably guide the gas in the FOUP 2 to the gas detector 30 .

One end of the second pipe portion 122b in the in-container cleaning device 110 is connected to the second bottom nozzle 21b communicating with the second bottom hole 2eb of the hoop 2 . The other end of the second pipe portion 122b is connected to a cleaning gas tank (not shown), and the control portion 120 controls the second pipe portion 122b, the second bottom nozzle 21b, and the second bottom hole 2eb. A cleaning gas can be introduced into the hoop 2 via the hoop 2 . The control unit 120 introduces the cleaning gas through the second bottom hole 2eb of the hoop 2 to supplement the gas discharged from the first bottom hole 2ea for detection by the gas detection unit 30, Cleanliness inside the hoop 2 can be improved. Therefore, the second bottom nozzle 21b and the second pipe portion 122b function as gas introducing means capable of introducing the cleaning gas into the hoop 2 .

The in-container cleaning device 110 has an acceleration detector 142 that detects the acceleration of the hoop 2 . The acceleration detection section 142 is provided on the upper surface of the slide table 14b, which is the hoop installation surface of the mounting section 14. As shown in FIG. The tip of the acceleration detection section 142 is biased toward the bottom surface 2e of the hoop 2, and the acceleration detection section 142 detects the acceleration of the hoop 2 by moving following the movement of the in-container cleaning device 110. do. However, the acceleration detection unit 142 is not limited to this, and any type of acceleration sensor such as a piezoelectric acceleration sensor, a servo acceleration sensor, or a strain gauge acceleration sensor may be used. A detection output of the acceleration detection unit 142 is input to the control unit 120 .

The in-container cleaning device 110 has an external detection unit 143 that detects at least one of the components of the external gas surrounding the hoop 2 and the cleanliness of the gas. Examples of the external detection unit 143 include an oxygen concentration meter, a moisture (water vapor) concentration meter, a nitrogen concentration meter, a particle counter, and the like, but are not particularly limited. The detection output of the external detection section 143 is also input to the control section 120 in the same manner as the detection output of the acceleration detection section 142 .

The in-container cleaning device 110 is provided in the cleaning chamber 11 and has a second gas detection unit 144 that detects at least one of the components of the gas inside the cleaning chamber 11 and the cleanliness of the gas. Examples of the second gas detection unit 144 include an oxygen concentration meter, a moisture (water vapor) concentration meter, a nitrogen concentration meter, a particle counter, and the like, but are not particularly limited. As shown in FIGS. 4A and 4B, the second gas detection unit 144 detects a gas that detects the cleanliness and the like in the hoop 2 when the cleaning chamber 11 and the inside of the hoop 2 are in communication. It also functions as a detector. The detection output of the second gas detection section 144 is also input to the control section 120 in the same manner as the detection output of the gas detection section 30 .

The control unit 120 controls the introduction of cleaning gas into the FOUP 2 using the outputs of the acceleration detection unit 142, the external detection unit 143, and the second gas detection unit 144 in addition to the output of the gas detection unit 30. be able to. For example, when acceleration exceeding a predetermined value is detected by the acceleration detection unit 142, the control unit 120 changes the amount of cleaning gas emitted from the first gas discharge means 16a and the second gas discharge means 16b. By stopping the release of gas, the vibration of the hoop 2 can be suppressed, and the inside of the hoop 2 can be kept in a highly clean state with few particles.

For example, when the external detection unit 143 detects that the cleanliness of the surrounding environment of the FOUP 2 and the cleaning chamber 11 is lower than a predetermined value, the control unit 120 changes the moving speed of the slide table 14b in the placement unit 14. , or the moving speed of the lid 4 or the like by the opening/closing mechanism 15 can be reduced. As a result, the control unit 120 suppresses variations in airtightness at the connecting portion between the hoop 2 and the cleaning chamber 11, and prevents external gas from flowing into the hoop 2 from the connecting portion during the cleaning operation. Therefore, it is possible to prevent the problem of worsening the cleanliness inside the hoop 2 .

6, for example, the control unit 120 uses the output of the second gas detection unit 144 instead of the output of the gas detection unit 30 to determine whether the inside of the FOUP 2 is clean. (or not clean). In addition, the control unit 120 changes the flow rate of the cleaning gas discharged from the indoor gas discharge unit 16 into the hoop 2 according to the difference in output between the second gas detection unit 144 and the gas detection unit 30. good too.

The in-container cleaning device 110 controls the introduction of the cleaning gas into the hoop 2 using outputs from a plurality of different detection units 30, 142, 143, and 144, thereby controlling the cleanliness inside the hoop 2. can be increased exponentially. Further, the in-container cleaning apparatus 110 can output the outputs from the detection units 30, 142, 143, and 144 to a host computer that can communicate with the load port device 51 and the processing device 50 in the semiconductor factory. By using the data from the in-container cleaning apparatus 110, the host computer can better manage the quality of the wafers 1 processed in the semiconductor factory. Further, the in-container cleaning apparatus 110 receives information about the processing history of the wafer 1 in the FOUP 2 transported to the mounting section 14 via the host computer, and uses the history information of the wafer 1 to may control the introduction of the cleaning gas to the .

REFERENCE SIGNS LIST 1 wafer 2 hoop 2b container main opening 2e bottom surface 2ea first bottom hole 2eb second bottom hole 4 lid 10, 110 container internal cleaning device 11 cleaning chamber 11a front wall 11aa... Apparatus opening 11b... Side wall part 11c... Back wall part 11d... Top wall part 11e... Bottom wall part 13... Door 14... Mounting part 14a... Fixed base 14b... Slide table 14c... Positioning pin 15... Opening/closing mechanism 16... Indoor gas discharge unit 16a First gas discharge means 16b Second gas discharge means 18 Discharge port 19 Discharge port opening/closing mechanism 20, 120 Control unit 20a Storage unit 21a First bottom nozzle 21b Second 2 bottom nozzle 22... piping part 22a, 122a... first piping part 22b, 122b... second piping part 22c... third piping part 30... gas detector 50... processor 51... load port device 142... acceleration detector 143 ... external detection section 144 ... second gas detection section 146 ... discharge pump

Claims (7)

A container cleaning apparatus for cleaning the inside of a wafer transport container having a container main opening from which wafers can be taken out,
a mounting section for mounting the wafer transport container;
a cleaning chamber comprising a device opening that connects to the container main opening;
an opening/closing mechanism that opens and closes a lid that closes the container main opening and a door that closes the apparatus opening, and communicates the inside of the wafer transfer container with the cleaning chamber;
a gas introducing means capable of introducing a cleaning gas into the wafer transfer container;
a gas detection unit that detects at least one of gas components and gas cleanliness in the wafer transfer container;
a control unit that controls introduction of the cleaning gas into the wafer transfer container using the output of the gas detection unit;
has
A transport device for taking out and transporting the wafer from the wafer transport container and a processing device for processing the transported wafer are not provided, and are provided separately from at least the processing device ,
The mounting portion includes at least two bottom nozzles each communicating on one side with at least two bottom holes formed in the bottom surface of the wafer transport container, and a second bottom nozzle communicating with the other side of the at least one bottom nozzle. 1 piping section, a second piping section communicating with the other side of at least one other bottom nozzle, and at least one of the first piping section and the second piping section to flow out of the wafer transport container and a third piping portion for discharging gas,
The gas detection unit is provided at a connection portion where the first pipe portion, the second pipe portion and the third pipe portion are connected,
The gas detection unit connects the first pipe unit and the second pipe unit to return the outflowing gas to the wafer transfer container, and at least one of the first pipe unit and the second pipe unit. is connected to the third pipe portion to discharge the outflowing gas . The gas detection unit detects at least one of gas components and gas cleanliness in the wafer transfer container by detecting gas that has flowed out from the inside of the wafer transfer container through the bottom hole. The in-container cleaning apparatus according to claim 1, characterized in that: further comprising an acceleration detection unit for detecting acceleration of the wafer transfer container;
3. The in-container cleaning apparatus according to claim 1, wherein said control section further uses the output of said acceleration detection section to control introduction of said cleaning gas into said wafer transfer container. 4. The in-container cleaning apparatus according to claim 3, wherein the acceleration detecting section is provided on the mounting surface of the wafer transfer container in the mounting section. 3. The gas introducing means further has an indoor gas discharge part provided inside the cleaning chamber and capable of switching between clean dry air and an inert gas as the cleaning gas and discharging the cleaning gas. The in-container cleaning apparatus according to any one of claims 1 to 4. further comprising an external detection unit that detects at least one of a component of gas outside the wafer transfer container and a cleanliness level of the gas;
6. The container interior cleaning according to any one of claims 1 to 5, wherein the control unit further uses the output of the external detection unit to control the introduction of the cleaning gas into the wafer transfer container. Device. further comprising a storage unit that stores the output of the gas detection unit;
The control unit is capable of changing a control condition for introducing the cleaning gas into the wafer transfer container by using the past output of the gas detection unit stored in the storage unit. The container interior cleaning apparatus according to any one of claims 1 to 6.

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