Dust removal room

Abstract

To provide a dedusting chamber capable of suppressing the deterioration of cleanness of a clean room.SOLUTION: A dedusting chamber provided in an entrance route to a clean room is equipped with a door leading to the clean room, an air shower mechanism that blows clean air into the dedusting chamber and sprays it to workers in the dedusting chamber to remove dust, a suction mechanism that has a suction port that is connected to the dedusting chamber and sucks gas in the dedusting chamber, and a particle counter that measures the size and number of particles included in the gas sucked by the suction mechanism. If the cleanness of the gas indicated by the size and number of the particles included in the gas measured by the particle counter does not satisfy a criterion, the door leading to the clean room is not opened, or the locking of the door is not released, so that the workers cannot enter the clean room.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a dust removal chamber installed at the entrance and exit of a clean room, which is equipped with an air shower that sprays air at workers to remove dust and the like adhering to the workers, and the door to the clean room is opened after the air spray is completed. [Background technology]

[0002] Device chips used in electronic devices such as mobile phones and computers are manufactured in clean rooms where dust and other particles are removed and the cleanliness is extremely high. To continue to stably manufacture high-quality device chips, it is necessary to maintain a high level of cleanliness in the clean room at all times. Therefore, a dust removal chamber is installed at the entrance and exit of the clean room, where air is sprayed on workers before they enter the clean room to remove dust and other particles adhering to the workers and their clean suits (see Patent Documents 1, 2, and 3). [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Publication No. 5-106887 [Patent Document 2] Japanese Patent Application Publication No. 9-229441 [Patent Document 3] Japanese Unexamined Patent Publication No. 63-44982 Summary of the Invention [Problem to be solved by the invention]

[0004] The dust removal chamber is equipped with an air shower mechanism that sprays clean air at high pressure onto workers. In the dust removal chamber, air is sprayed toward workers from multiple punker louvers that function as nozzles. However, since the area over which the sprayed air can travel while maintaining effective momentum is limited, workers in the dust removal chamber must move their bodies in a specific sequence to ensure that the air hits every corner of the surface of their clean suits and that they are fully exposed to the air spray.

[0005] However, there are cases where dust and the like are not sufficiently removed by the air, such as when a worker does not move his / her body appropriately, or when the worker or the clean suit is extremely contaminated. When air is sprayed at a predetermined time in the dust removal room, the worker enters the clean room through the door, and the clean room becomes contaminated by the worker from whom dust and the like has not been sufficiently removed, which causes a problem of a decrease in the cleanliness of the clean room.

[0006] The present invention has been made in consideration of such problems, and its purpose is to provide a dust removal chamber that can sufficiently remove dust and other particles adhering to workers and clean suits, thereby preventing a decrease in the cleanliness of the clean room. [Means for solving the problem]

[0007] According to one aspect of the present invention, there is provided a dust removal chamber provided on an entrance path to a clean room, the dust removal chamber comprising: a door leading to the clean room; an air shower mechanism for blowing clean air into the dust removal chamber and showering it on workers in the dust removal chamber to remove dust; a suction mechanism having a suction port connected to the dust removal chamber and for suctioning gas in the dust removal chamber; and a particle counter for measuring the size and number of particles contained in the gas suctioned by the suction mechanism. an imaging unit that takes an image of the worker in the dust removal chamber and creates an image that can be used to identify the adhesion position of the particle; and a monitor that displays the adhesion position of the particle. Equipped with The adhesion position of the particle identified based on the captured image can be displayed on the monitor, The dust-free room is characterized in that, if the cleanliness of the gas indicated by the size and number of particles contained in the gas measured by the particle counter does not satisfy the judgment criteria, the door leading to the clean room will not be opened or the door will not be unlocked, preventing the worker from entering the clean room. [Effects of the Invention]

[0009] A dust removal chamber according to one aspect of the present invention includes an air shower mechanism that showers clean air on workers in the chamber, a suction mechanism that sucks in gas from the dust removal chamber, and a particle counter that measures the size and number of particles contained in the gas sucked in by the suction mechanism. If the cleanliness of the gas, as indicated by the size and number of particles contained in the gas, does not meet the criteria, the door leading to the clean room will not open or the door will not be unlocked. This means that workers cannot enter the clean room.

[0010] Therefore, with the dust removal chamber according to one aspect of the present invention, workers who have not been sufficiently free of dust and other contaminants will not enter the clean room and contaminate it. Workers who are unable to enter the clean room can take measures such as changing their clean suits or moving their bodies appropriately within the dust removal chamber to ensure that the room is in a sufficiently dust-free state before entering the clean room.

[0011] Therefore, according to one aspect of the present invention, a dust removal chamber is provided that can sufficiently remove dust and the like adhering to workers and clean suits, and can prevent a decrease in the cleanliness of the clean room. [Brief explanation of the drawings]

[0012] [Figure 1] FIG. 3 is a cross-sectional view schematically showing a dust removal chamber. [Figure 2] FIG. 2 is a block diagram schematically illustrating a flow path of a particle counter. [Figure 3] 10 is a flowchart showing an example of a control flow of a control unit. DETAILED DESCRIPTION OF THE INVENTION

[0013] An embodiment of the present invention will be described with reference to the accompanying drawings. The dust removal chamber according to this embodiment is installed on the entrance path to a clean room provided in a semiconductor device, pharmaceutical, or food manufacturing plant, etc. The clean room is an area where dust and other particles contained in the air inside the room have been removed to a predetermined degree, and is a room managed to maintain a cleanliness level appropriate for its purpose.

[0014] To maintain the cleanliness of a clean room, it is important to prevent dust and other contaminants from entering from the outside. To achieve this, it is best to prevent people and objects that could be sources of contamination from entering the clean room. However, workers must enter the clean room to carry items in and out of the clean room, and to perform maintenance on the various devices installed in the clean room.

[0015] Therefore, to prevent dust and other particles adhering to workers from spreading throughout the clean room, workers wear clean suits that cover their entire body when entering the clean room. To remove dust and other particles adhering to the surface of the clean suit, a dust removal chamber is provided at the entrance and exit of the clean room, where high-pressure air is sprayed onto the workers entering the clean room to remove the dust and other particles.

[0016] 1 is a cross-sectional view schematically showing a dust removal chamber 2 according to this embodiment. The dust removal chamber 2 includes an internal space 4 where a worker 11 enters and is subjected to a spray of high-pressure air, a door 10 connecting the dust removal chamber 2 to a clean room, and an air flow path 6 through which clean air supplied to the internal space 4 flows.

[0017] The dust removal chamber 2 is equipped with a plurality of nozzles 8 called punker louvers on the ceiling 4a and side walls 4b of the internal space 4, and clean air flowing through the air flow path 6 is sprayed from the nozzles 8 into the internal space 4. The floor 4c of the internal space 4 of the dust removal chamber 2 is made of a mesh structure 14 made of stainless steel or the like, and the air that has taken in dust and the like adhering to the worker passes through the mesh structure 14 and proceeds to the air flow path 16 through which used air flows.

[0018] The dust removal chamber 2 further includes a pump (fan) 18 that sucks up used air flowing through the air flow path 16, and a filter 20 that purifies the air by removing dust and the like from the air sucked up by the pump 18. The filter 20 is, for example, a HEPA filter. The clean air sucked up by the pump 18 and purified by the filter 20 flows through the air flow path 6 as clean air and is supplied from the nozzle 8 to the internal space 4 of the dust removal chamber 2.

[0019] In this way, the dust removal chamber 2 blows clean air into the internal space 4 of the dust removal chamber 2 and showers it on the worker 11 who has entered the internal space 4 of the dust removal chamber 2. That is, the dust removal chamber 2 is equipped with an air shower mechanism made up of an air flow path 16, a pump 18, a filter 20, an air flow path 6, an injection port 8, etc. When the worker 11 enters the internal space 4, the pump 18 is operated to circulate the air, and the clean air is blown onto the worker 11 by the air shower mechanism, removing dust and the like adhering to the worker 11.

[0020] Generally, in the dust removal room 2, air is sprayed onto the worker 11 for a predetermined time by an air shower mechanism. After the predetermined time has elapsed, the door 10 leading to the clean room opens or the lock on the door 10 is released, allowing the worker 11 to enter the clean room. There is no particular limit to the time for which the air shower mechanism sprays air onto the worker 11, but it is set to a time that is sufficient to sufficiently remove dust and the like adhering to the worker 11.

[0021] However, the area over which the air sprayed from the nozzle 8 made up of the puncture louvers toward the worker 11 can travel while maintaining effective momentum is limited. Therefore, if the worker 11 who has entered the internal space 4 simply stands still while receiving the air spray, only a limited area on the surface of the worker 11 and the clean suit will be cleaned, and there will be a problem that dust and the like will remain in areas that do not receive a sufficient amount of air spray.

[0022] Therefore, while receiving the air spray, the worker 11 is required to perform predetermined actions such as raising his / her arms upward, turning in place, or tapping the clean suit with his / her hands so that the air hits the entire surface of the body, including the armpits and crotch, and dust and the like are sufficiently removed. However, the worker 11 does not always perform appropriate actions in the dust removal chamber 2, and even if dust and the like adhering to the worker 11 has not been sufficiently removed, the worker 11 may be able to enter the clean room after the predetermined time has elapsed.

[0023] Furthermore, while the worker 11 temporarily leaves the clean room and returns to the clean room, serious contamination may adhere to the clean suit outside the clean room. Therefore, the contamination may not be sufficiently removed by simply subjecting the worker 11 to air injection in the dust removal chamber 2 according to the normal procedure. Even in this case, once air injection is performed in the dust removal chamber 2 for a predetermined time, the worker 11 will be able to enter the clean room.

[0024] Therefore, in the dust removal room 2 according to this embodiment, it is determined whether or not dust and the like adhering to the worker 11 and the clean suit has been sufficiently removed, and if it is determined that the dust and the like has not been sufficiently removed, the door 10 is not opened or the lock of the door 10 is not released. In other words, the worker 11 is not allowed to enter the clean room.

[0025] The following description will focus on the configuration related to the determination operation of the dust removal chamber 2. The dust removal chamber 2 has a suction port 22a connected to the dust removal chamber 2, and is equipped with a suction mechanism (pump) 22 that sucks gas from the internal space 4 of the dust removal chamber 2, and a particle counter 26 that measures the size and number of particles contained in the gas sucked by the suction mechanism 22. The suction mechanism (pump) 22 and the particle counter 26 are connected by a pipe 24.

[0026] Alternatively, the dust removal chamber 2 may be provided with a suction mechanism 22 in the particle counter 26. Fig. 2 is a block diagram showing a schematic configuration of the particle counter 26 equipped with the suction mechanism 22. The particle counter 26 is equipped with a detection unit 34 that measures the gas supplied through the piping 24 and determines the number and size of particles contained in the gas.

[0027] There are no particular limitations on the configuration of the particle counter 26 and the detection unit 34, but for example, a light scattering method is preferably used, in which a laser beam is irradiated onto the gas to be measured and scattered light generated when the laser beam strikes fine particles contained in the gas is detected. In a particle counter 26 using the light scattering method, the detection unit 34 irradiates the gas with laser beam, detects the scattered light with a photodiode, converts it into an electrical signal, and measures the number and size of the particles from the electrical signal. Information such as the size and number of particles is reflected in this electrical signal.

[0028] Each component of the dust removal chamber 2 is controlled by a control unit 28. The control unit 28 is configured by a computer including, for example, a processing device such as a CPU or a microprocessor, and a storage device such as a flash memory or a hard disk drive. The control unit 28 operates the processing device in accordance with software such as a program stored in the storage device, thereby functioning as a concrete means in which the software and the processing device (hardware resources) work together.

[0029] The control unit 28 has a memory unit 30 which is configured as a storage device and stores various information and software such as programs. For example, the memory unit 30 stores the procedures and conditions of the dust removal process for the worker 11 to be carried out in the dust removal room 2, and the control unit 28 controls the pump 18, the door 10, etc. based on the procedures and conditions of the dust removal process stored in the memory unit 30.

[0030] The control unit 28 also includes a determination unit 32 that determines whether or not the worker 11 is permitted to enter the room based on the cleanliness of the gas indicated by the size and number of particles contained in the gas measured by the particle counter 26. A determination threshold (determination criterion) for the cleanliness used by the determination unit 32 for determination is stored in the memory unit 30, for example.

[0031] If the cleanliness of the gas measured by the particle counter 26 during the predetermined time while the air is being sprayed onto the worker 11 exceeds the cleanliness threshold (criterion), the judgment unit 32 allows the worker 11 to enter the clean room. In this case, after the spraying of the hair onto the worker 11 is completed, the control unit 28 opens the door 10 or unlocks the door 10, allowing the worker 11 to enter the clean room.

[0032] On the other hand, if the cleanliness of the gas measured by the particle counter 26 while air is being sprayed toward the worker 11 for a predetermined time does not satisfy the cleanliness that is the judgment threshold (criterion), the judgment unit 32 does not allow the worker 11 to enter the clean room. In this case, the control unit 28 does not open the door 10 or unlock the door 10, thereby not allowing the worker 11 to enter the clean room.

[0033] Then, the control unit 28 either injects additional air into the worker 11 until the cleanliness of the measured gas meets the judgment threshold (criterion), or warns the worker 11 that it is not possible to grant permission to enter the room after the air injection has finished, and urges the worker 11 to make improvements.

[0034] For example, a monitor 12 configured with a liquid crystal panel or an OLED panel may be provided on the side wall 4b of the internal space 4 of the dust removal chamber 2. The monitor 12 displays various information to provide the information to the operator 11. The control unit 28 may then cause the monitor 12 to display the determination result by the determination unit 32, the measured cleanliness of the gas that is the basis for the determination, and other information.

[0035] If the worker 11 is not permitted to enter the clean room, he / she considers ways to improve the situation by referring to the judgment result and the cleanliness of the gas displayed on the monitor 12. For example, the worker 11 may go outside the dust removal chamber 2 to inspect the clean suit he / she is wearing and remove any dirt adhering to it, or change the clean suit. Then, the worker 11 again enters the internal space 4 of the dust removal chamber 2, where he / she is sprayed with air and is judged by the judgment unit 32 as to whether or not he / she is permitted to enter the room.

[0036] The dust removal chamber 2 according to this embodiment can thereby thoroughly remove dust and other particles adhering to the worker 11 or the clean suit, suppressing a decrease in the cleanliness of the clean room due to the worker 11 entering the clean room, and maintaining the cleanliness of the clean room at a predetermined level or above.

[0037] Even if the cleanliness of the gas detected by particle counter 26 while air is being sprayed on worker 11 satisfies the criteria, the clean room may become more contaminated than expected if worker 11 continues to enter the clean room. For example, if worker 11 does not move his / her body in the prescribed procedure in internal space 4 of dust removal chamber 2 and the air does not hit a specific area of ​​the clean suit properly, the cleanliness of the gas measured by particle counter 26 may not decrease.

[0038] In this way, even if contamination remains in a specific area of ​​the clean suit, if the cleanliness of the gas measured by particle counter 26 exceeds the judgment threshold (criterion), control unit 28 will open door 10 or unlock door 10. Therefore, if judgment is made based only on the cleanliness of the gas measured by particle counter 26, there is a risk that workers 11 who should not be allowed to enter the clean room will be allowed to enter.

[0039] Therefore, the determination unit 32 may further refer to other information to determine whether or not the worker 11 is permitted to enter the clean room. That is, the criteria by which the determination unit 32 determines whether or not the worker 11 is permitted to enter the clean room are not limited to the cleanliness of the gas detected using the particle counter 26.

[0040] For example, the dust removal chamber 2 may be provided with an imaging unit 38 in the internal space 4 that captures an image of the worker 11, as shown in Fig. 1. The imaging unit 38 includes an optical element such as a CCD sensor or a CMOS sensor. The imaging unit 38 is connected to the control unit 28, and under the control of the control unit 28, captures an image of the internal space 4 of the dust removal chamber 2 to form a captured image, and transmits the captured image to the control unit 28. The determination unit 32 of the control unit 28 may determine whether or not to allow the worker 11 to enter the chamber, by referring to the captured image created by the imaging unit 38.

[0041] Next, we will explain an example of a determination method of the determination unit 32 based on the captured image created by the imaging unit 38. For example, the control unit 28 performs image processing on the captured image to detect dirt adhering to the surface of the clean suit worn by the worker 11. Since clean suits are generally plain, if a foreign object is adhering to the surface of the clean suit, the foreign object can be easily detected from the appearance of the clean suit.

[0042] The control unit 28 continues to create captured images using the imaging unit 38 while air is being sprayed at the worker 11 in the dust removal chamber 2, and detects the presence or absence of foreign matter on the surface of the clean suit. If a foreign matter is detected, the control unit 28 creates information such as the location of the foreign matter on the clean suit and its size based on the captured images. The memory unit 30 stores information about foreign matter that is acceptable as a judgment condition, and the judgment unit 32 refers to the judgment condition and does not allow the worker 11 to enter the chamber if the detected foreign matter is not acceptable.

[0043] If the foreign matter adhering to the clean suit of the worker 11 is unacceptable and the judgment unit 32 judges that the worker 11 should not be permitted to enter the clean room, the control unit 28 causes the monitor 12 to display information such as the position and size of the foreign matter along with the judgment result. The monitor 12 may also display countermeasures corresponding to the state of the foreign matter. The worker 11 then takes action to improve the situation based on the information displayed on the monitor 12. Thereafter, the worker 11 is again subjected to the air injection and judged by the judgment unit 32.

[0044] Furthermore, the imaging unit 38 can also be used to evaluate how the worker 11 is wearing the clean suit. For example, if the worker 11 is not wearing the clean suit properly and the skin or hair is excessively exposed from the clean suit, this can become a source of dust when the worker 11 enters or leaves the clean room. Therefore, the control unit 28 evaluates how the worker 11 is wearing the clean suit from the images captured by the imaging unit 38. Then, the determination unit 32 does not permit the worker 11 to enter or leave the clean room if the wearing is inappropriate.

[0045] Next, another example of the determination method of the determiner 32 using the imaging unit 38 will be described. The controller 28 causes the imaging unit 38 to continuously create captured images while air is being sprayed at the worker 11 in the dust removal chamber 2, and observes the body movements of the worker 11. The memory unit 30 stores information about the body movements of the worker 11 that are acceptable as a determination condition, and the determiner 32 refers to the determination condition and, if the observed body movements of the worker 11 are not acceptable, does not permit the worker 11 to enter the chamber.

[0046] If the worker 11 is not moving his / her body in an appropriate manner in the dust removal chamber 2, the control unit 28 displays the judgment result, as well as an image of the worker 11 moving his / her body and information such as the correct way to move his / her body, on the monitor 12. The worker 11 then improves the situation by moving his / her body appropriately based on the information displayed on the monitor 12. Thereafter, the worker 11 is judged by the judgment unit 32 while receiving the air injection.

[0047] For example, if it is specified that the worker 11 must raise both arms to a predetermined height and turn a predetermined number of times in the dust removal room 2, the determination unit 32 determines from the captured image whether the worker 11 has raised both arms to the predetermined height and turned a predetermined number of times. If the determination unit 32 determines that the worker 11 has not raised both arms to the predetermined height, a message encouraging the worker 11 to raise both arms higher is displayed on the monitor 12.

[0048] Regardless of the result of the determination by the determination unit 32, the control unit 28 may continue to display on the monitor 12 the image of the worker 11 captured by the imaging unit 38 and information on appropriate body movements. Also, the control unit 28 may continue to display on the monitor 12 information on the cleanliness of the gas measured by the particle counter 26. In this case, the control unit 28 may encourage the worker 11 to come up with ideas for improving the way he moves his body in the internal space 4 and the control method of the dust removal chamber 2 so as to further reduce dust and the like brought into the clean room.

[0049] In this way, by using the imaging unit 38, it is possible to evaluate foreign matter adhering to the clean suit, the manner in which the clean suit is worn, and the body movements of the worker 11, and to use these as criteria to determine whether or not the worker 11 should be allowed to enter the clean room. Then, dust and the like can be sufficiently removed from the worker 11 and the clean suit before they enter the clean room, reducing the amount of dust and the like brought into the clean room and maintaining the cleanliness of the clean room at a predetermined level or above.

[0050] Finally, we will explain the control flow of the control unit 28 of the dust removal chamber 2 according to this embodiment, that is, the flow of the dust removal operation in the dust removal chamber 2. Fig. 3 is a flowchart showing an example of the control flow of the dust removal chamber 2 controlled by the control unit 28.

[0051] First, when the worker 11 enters the internal space 4 of the dust removal chamber 2, the control unit 28 activates the pump 18 to start spraying air from the nozzle 8 toward the worker 11 (S10). The control unit 28 operates the pump 18 at a predetermined output for a predetermined time in accordance with the operating conditions stored in the memory unit 30. The control unit 28 activates the suction mechanism 22 to suck in gas from the internal space 4 of the dust removal chamber 2, and measures the sucked gas using the particle counter 26 (S20).

[0052] The determination unit 32 of the control unit 28 determines whether or not the cleanliness of the gas indicated by the size and number of particles contained in the gas measured by the particle counter 26 meets the determination criteria (S30). If the cleanliness of the gas meets the determination criteria, the operator 11 is permitted to enter the clean room.

[0053] In this case, after the dust removal operation has been performed for a predetermined time, the control unit 28 stops the pump 18 and terminates the spray of air toward the worker 11 (S40). Thereafter, the control unit 28 opens the door 10 leading to the clean room or unlocks the door 10, allowing the worker 11 to enter the clean room (S51).

[0054] On the other hand, if the cleanliness of the gas detected by the particle counter 26 does not meet the criteria (S30), the operator 11 is not permitted to enter the clean room. In this case, the control unit 28 does not open the door 10 or unlock the door 10 (S52). Then, after the dust removal operation has been performed for a predetermined time, the control unit 28 extends the operation of the pump 18 to perform additional dust removal operation. Alternatively, the control unit 28 warns the operator 11 of the determination result and urges him or her to make improvements. By operating in this manner, the dust removal room 2 prevents a decrease in the cleanliness of the clean room.

[0055] The present invention is not limited to the above-described embodiment and can be practiced with various modifications. For example, in the above-described embodiment, the control unit 28 of the dust removal chamber 2 controls each component of the dust removal chamber 2, and the determination unit 32 of the control unit 28 determines whether or not the worker 11 is permitted to enter the clean room. However, one aspect of the present invention is not limited to this.

[0056] That is, whether or not the worker 11 is permitted to enter the clean room may be determined by a device other than the control unit 28 of the dust removal room 2. For example, if the clean room is installed in a manufacturing factory for semiconductor devices or the like, and the manufacturing factory is controlled by a control computer, the control computer may control the dust removal room 2 to determine whether or not the worker 11 is permitted to enter the clean room.

[0057] If a particle counter 26 is connected to the dust removal chamber 2, and if an imaging unit 38 is installed in the internal space 4 of the dust removal chamber 2, then based on the information sent from these, a device other than the control unit 28 of the dust removal chamber 2 can determine whether or not the worker 11 is permitted to enter the clean room.

[0058] In addition, the structures, methods, etc. according to the above-described embodiments and modifications can be modified as appropriate without departing from the scope of the present invention. [Explanation of symbols]

[0059] 2 Dust removal room 4. Interior space 4a Ceiling 4b side wall 4c floor surface 6,16 Air flow path 8 injection port 10 Doors 11 Workers 12 monitors 14 Mesh structure 18 Pump 20 filters 22 Suction mechanism 22a Suction port 24 Piping 26 Particle Counter 28 Control Unit 30 Storage section 32 Judgment section 34 Detector 38 Imaging unit

Claims

[Claim 1] A dust removal room provided on an entrance path to a clean room, a door leading to the clean room; an air shower mechanism that blows clean air into the dust removal chamber and showers the air on workers in the dust removal chamber to remove dust; a suction mechanism having a suction port connected to the dust removal chamber and configured to suck gas from the dust removal chamber; a particle counter that measures the size and number of particles contained in the gas sucked by the suction mechanism; an imaging unit that takes an image of the worker in the dust removal chamber and creates an image that can be used to identify the location where the particles are attached; a monitor that displays the adhesion position of the particle; The adhesion position of the particle identified based on the captured image can be displayed on the monitor, A dust-free room characterized in that, if the cleanliness of the gas indicated by the size and number of particles contained in the gas measured by the particle counter does not meet the judgment criteria, the door leading to the clean room will not be opened or the door will not be unlocked, and the worker will not be able to enter the clean room.

Images