Storage device

Abstract

The utility model discloses a storage device. The storage device comprises a storage area, a transfer area, a gas filtering system and an air return system. Wherein the accommodating area is used for accommodating the plurality of semiconductor elements, and the transfer area and the accommodating area are independent of each other in space but can be selectively communicated with each other. The transfer area is used for receiving one of the plurality of semiconductor elements from the outside to the storage area, or transferring one of the plurality of semiconductor elements from the storage area to the outside. The gas filtering system is used for providing clean gas, and the air return system is in gas connection with the gas filtering system, so that the clean gas forms a gas circulation loop in the storage area and the transfer area respectively.

Description

Technical Field

[0001] This utility model relates to a storage device for effectively improving the cleanliness of the storage space for semiconductor components, thereby reducing contamination of semiconductor components during storage. It can be used to directly store exposed semiconductor components and increase the storage capacity of the storage device. Background Technology

[0002] Semiconductor components are used not only in everyday consumer products like smartphones, automobiles, and networks, but also, with the development of 5G communication, AI technology, and the Internet of Things (IoT), have become a key foundation for many technology industries, enriching and facilitating people's lives. Driven by technological advancements, the line diameter of semiconductor circuit patterns has evolved from the micrometer level to the nanometer level. To address the contamination caused by tiny particles such as dust in the environment and harmful gases released during manufacturing processes on semiconductor components (such as photomasks, wafers, LCD panels, and filters), contamination control measures during storage, transportation, and manufacturing have become increasingly stringent.

[0003] In semiconductor manufacturing plants, to maintain cleanliness during the manufacturing process, the current practice is to design cleanrooms, which mainly use airflow to create a closed environment. Air filter units (FFUs) generate clean air to remove the dirty air from the original environment, and then filter the dirty air to achieve a cleanroom environment. However, because the cleanroom environment is relatively large, the particles and harmful gases generated by various devices can interfere with each other due to airflow circulation. Therefore, it is generally difficult to effectively control the cleanliness of a cleanroom, or it may require a significant increase in the cost of filtration equipment to maintain cleanliness. Therefore, when storing and transporting semiconductor components in a cleanroom, a separate component container with an independent clean environment is required.

[0004] Taking a photomask as an example, it is used to transfer circuit patterns onto the surface of a wafer through a lithography process. Due to the aforementioned miniaturization of circuit patterns, defects in the photomask used for transferring circuit patterns can cause open circuits, short circuits, or distortions in the circuit patterns. It is known that photomask defects are caused by surface contamination, such as the accumulation of harmful pollutants like particles, chemicals, or gaseous molecules in the environment. Defects such as particle adhesion or smog on the photomask surface can occur. To maintain the cleanliness of the photomask surface, photomasks are generally stored or transported in a component container, such as the SEMI standard photomask transport box (Reticle SMIF). Pods, RSPs, and ultraviolet photomask delivery boxes (EUVPODs) are examples of storage devices. During storage, the container holding the semiconductor components is placed in a storage device (Stocker). However, the volume of the component container is much larger than the semiconductor components it contains. For example, the volume of a photomask delivery box is generally 3 to 10 times that of the photomask. This significantly reduces the capacity of the storage device, increases its footprint, and requires more storage devices. In order to maintain the internal environment of each component container, an inflation system and inflation tray are usually designed inside the storage device to support and inflate multiple component containers. This makes the structure of the storage device more complex, increases its manufacturing and maintenance costs, and also increases the chance of contamination inside the storage device.

[0005] In other words, existing storage devices are not directly used to store semiconductor components, which results in complex structures and large sizes, increasing their manufacturing and maintenance costs. Therefore, how to solve the aforementioned problems is what businesses and users expect, and it is also the solution that this utility model seeks to explore.

[0006] In view of the above-mentioned shortcomings, the inventor of this case believed that it was necessary to make corrections. Therefore, based on his many years of experience in related technologies and product design and manufacturing, and adhering to the concept of good design, he studied and improved the above-mentioned shortcomings. After continuous efforts in trial and error, he finally successfully developed a storage device to overcome the troubles and inconveniences caused by the inability of existing storage devices to directly store semiconductor components. Utility Model Content

[0007] Therefore, the main purpose of this utility model is to provide a storage device that can improve the cleanliness of the storage device and effectively maintain it, so that it can be used to directly store semiconductor components without being contaminated.

[0008] Another major objective of this utility model is to provide a storage device that can increase the storage capacity of semiconductor components while reducing the footprint of the storage device, thereby improving the flexibility of plant space utilization.

[0009] Another major objective of this utility model is to provide a storage device that simplifies the structure of the storage device, reduces the sources of pollution inside the storage device, and thus reduces the manufacturing and maintenance costs of the storage device.

[0010] To achieve the above objectives, this utility model provides a storage device for accommodating multiple semiconductor components. The storage device includes a storage area, a transfer area, a gas filtration system, and a return air system. The storage area is used to house the multiple semiconductor components, while the transfer area and the storage area are spatially independent but selectively connected. The transfer area is used to receive one of the multiple semiconductor components from the outside to the storage area, or to transfer one of the multiple semiconductor components from the storage area to the outside. The gas filtration system provides clean gas, and the return air system is connected to the gas filtration system, enabling the clean gas to form a gas circulation loop within both the storage area and the transfer area.

[0011] In one embodiment of the storage device of this utility model, a process area is further included, which can be selectively connected to the transfer area for performing a semiconductor process on one of the plurality of semiconductor elements.

[0012] In one embodiment of the storage device of this utility model, the return air system includes a first return air subsystem, which is set inside the storage area and has a mesh plate and at least one first return air channel. The mesh plate is set at the bottom of the storage area, and the gas in the first return air channel is connected to the gas filtration system, so that the clean gas forms a first gas circulation loop inside the storage area.

[0013] In one embodiment of the storage device of this utility model, the return air system includes a second return air subsystem, which is set inside the transfer zone and has a mesh plate and at least one second return air channel. The mesh plate is set at the bottom of the transfer zone, and the gas in the second return air channel is connected to the gas filtration system, so that the clean gas forms a second gas circulation loop inside the transfer zone.

[0014] In one embodiment of the storage device of this utility model, the return air system includes a third return air subsystem, which is set inside the process area and has a mesh plate and at least one third return air channel. The mesh plate is set at the bottom of the process area, and the gas in the third return air channel is connected to the gas filtration system, so that the clean gas forms a third gas circulation loop inside the process area.

[0015] In one embodiment of the storage device of this utility model, the gas filtration system includes a first gas filtration unit connected to a first return air channel, providing a first gas circulation loop for clean gas within the storage area.

[0016] In one embodiment of the storage device of this utility model, the gas filtration system includes a second gas filtration unit connected to a second return air channel, providing a second gas circulation loop for clean gas within the transfer area.

[0017] In one embodiment of the storage device of this utility model, the gas filtration system includes a third gas filtration unit connected to a third return air channel, providing clean gas in a third gas circulation loop within the process area.

[0018] After referring to the drawings and the embodiments described below, those skilled in the art will understand other objectives of the present invention, as well as the technical means and implementation of the present invention. Attached Figure Description

[0019] Figure 1 This is a schematic diagram of the appearance of the storage device of this utility model.

[0020] Figure 2 This is a schematic diagram of the storage device of this utility model, used to illustrate the device configuration and its relative relationships.

[0021] Figure 3 This is a top view of the storage device of this utility model, used to illustrate the internal structure of the storage area of ​​the cabin and its corresponding relationships.

[0022] Figure 4 This is a schematic diagram of the internal structure of the compartment in the storage device of this utility model, used to illustrate the internal structure of the storage area of ​​the compartment.

[0023] Figure 5 This is a schematic diagram of the internal structure of the storage device of this utility model from another perspective, illustrating the internal structure of the transfer area and the process area of ​​the storage device.

[0024] Explanation of reference numerals in the attached drawings: 100-Storage equipment; 10-Bucket; 101-Top plate; 102-Bottom plate; 103-Side plate; 105-Baffle; 200-Receiving area; 202-Filter membrane; 203-Mesh plate; 204-First return air space; 205-First return air duct; 20-Storage turret; 21-Storage position; 22-First filtration unit; 23-First environmental detection element; 300-Transfer area; 303-Mesh plate; 304-Second return air space; 305-Second return air duct; 30-Conveyor arm; 31-Second filtration unit; 32-Second environmental detection element; 33-Infeed channel; 34-Door panel; 400-Receiving and conveying area; 403- 404-Fourth Return Air Space; 40-Inlet / Outlet Port; 41-Inlet / Outlet Gate; 42-Box Opening Mechanism; 43-First Through-hole; 44-First Gate; 500-Process Area; 503-Screen Plate; 504-Third Return Air Space; 505-Third Return Air Channel; 50-Process Module; 51-Third Filter Unit; 52-Third Environmental Detection Element; 53-Second Through-hole; 54-Second Gate; 600-Maintenance Area; 60-Electrical Module; 61-Drive Module; 62-External Maintenance Door; 603-Screen Plate; 604-Fifth Return Air Space; 80-Control Unit; 81-Server; 85-Display Interface; A-Photomask; B-Component Container. Detailed Implementation

[0025] The following embodiments will explain the content of this utility model. These embodiments are not intended to limit the implementation of this utility model to any specific environment, application, or special method described in the embodiments. Therefore, the descriptions of the embodiments are for illustrative purposes only and are not intended to limit the scope of this utility model. It should be noted that in the following embodiments and drawings, elements not directly related to this utility model have been omitted and are not shown, and the dimensional relationships between the elements in the drawings are for ease of understanding only and are not intended to limit the actual scale.

[0026] This utility model provides a storage device. In the accompanying drawings illustrating specific embodiments and components of the photomask conveying box of this utility model, all references to front and back, left and right, top and bottom, upper and lower parts, and horizontal and vertical are for convenience of description only and are not intended to limit this utility model, nor to restrict its components to any position or spatial orientation. The dimensions specified in the drawings and specification may be varied according to the design and requirements of specific embodiments of this utility model without departing from its scope, and therefore are not limited to this structure in terms of coverage.

[0027] The storage device of this invention is used to directly store multiple semiconductor components. Please refer to [reference needed]. Figure 1 , Figure 2 and Figure 3As shown, the present invention takes a storage device 100 (Stocker) capable of accommodating multiple photomasks A as the main embodiment. The storage device 100 is composed of a cabin 10, which has a top plate 101, a bottom plate 102, and multiple side plates 103 surrounding the outline of the top plate 101 and the bottom plate 102. The interior of the cabin 10 is divided into at least one independent space for a storage area 200, a transfer area 300, and a receiving and sending area 400 by multiple partitions 105. The transfer area 300 can be selectively connected to the storage area 200 and the receiving and sending area 400. Furthermore, a control unit 80 is provided on the cabin 10. The control unit 80 includes at least one server 81 and at least one display interface 85. The control unit 80 and the cabin 10 can be designed as an integral part or separately. Furthermore, according to some embodiments, the interior of the cabin 10 is further divided into at least one process area 500, which is spatially independent of the storage area 200, the transfer area 300 and the receiving and sending area 400, but may be selectively connected to the transfer area 300.

[0028] One technical feature of this utility model is that a wafer storage turret 20 is provided in the storage area 200, installed between the top plate 101 and the bottom plate 102 of the cabin 10. The wafer storage turret 20 has multiple storage positions 21 for directly storing multiple semiconductor components, such as multiple exposed photomasks A. Please also refer to... Figure 3 , Figure 4 As shown, another technical feature of this utility model is that the cabin 10 is provided with a gas filtration system on the top plate 101 to provide a clean gas inside the cabin. In addition, a return air system is provided inside the cabin, and the gas is connected to the gas filtration system, so that the clean gas provided by the gas filtration system can form a gas circulation loop in each independent space inside the cabin.

[0029] In a specific implementation, the gas filtration system includes at least one first filter unit 22, which is connected to the control unit 80. This invention primarily uses two first filter units 22, each of which can be a fan filter unit (FFU), combining a blower and a high-efficiency filter for airflow circulation and filtration, used to deliver clean gas to the receiving area 200. The first filter unit 22 is located at the top of the receiving area 200 of the chamber 10, and the exhaust gas from the first filter unit 22 can communicate with the top of the receiving area 200 of the chamber 10. A filter membrane 202 (e.g., ...) is provided at the top of the receiving area 200. Figure 4 [As shown], this is to prevent particles from falling into the storage area 200 when the first filter unit 22 is shut down for replacement or maintenance. Furthermore, the return air system includes a first return air secondary system disposed in the storage area 200. Specifically, a mesh plate 203 is spaced above the base plate 102 in the storage area 200, such that a first return air space 204 is formed between the mesh plate 203 and the base plate 102. Figure 4 [C] Amplification section]. Also, the first return air secondary system has a first return air duct 205 [e.g., Figure 4 [D] The first return air duct 205 can be formed by a double-layer partition 105 on the inner wall of the storage area 200 or by an additional duct. Furthermore, the first return air duct 205 can be gas-connected to the first filter unit 22, so that the clean gas sent into the storage area 200 by the first filter unit 22, after passing through the storage turret 20, can enter the first return air space 204 through the mesh plate 203, and then flow back to the first filter unit 22 through the first return air duct 205. After being filtered by the first filter unit 22 to remove particles or harmful substances and restored to clean gas, it re-enters the storage area 200, forming a first gas circulation loop to save on the amount of clean gas used. Furthermore, the storage area 200 is provided with at least one first environmental detection element 23 connected to the control unit 80. The first environmental detection element 23 may include at least a temperature and humidity detector, a particulate detector and / or a harmful gas detector, so as to detect the real-time environmental conditions in the storage area 200.

[0030] like Figure 2 , Figure 3 and Figure 5 As shown, a transfer arm 30 connected to a control unit 80 is provided in the transfer area 300. The transfer arm 30 can grasp a photomask A, allowing the photomask A to move between the transfer area 300 and the receiving area 400, the process area 500, or the storage area 200. Alternatively... Figure 5 As shown, the gas filtration system has at least one second filtration unit 31 on the top plate 101 of the cabin 10 (e.g., Figure 1 As shown, it is electrically connected to the control unit 80. The second filter unit 31 can correspond to the gas communication chamber 10's transfer area 300 and deliver clean gas. The transfer area 300 is provided with a mesh plate 303 at intervals above the bottom plate 102, so that a second return air space 304 is formed between the mesh plate 303 and the bottom plate 102. Figure 5 [As shown]. Furthermore, the second return air space 304 is provided with at least one second return air duct 305 around the transfer area 300. The second return air duct 305 can be formed on the inner wall of the transfer area 300 by a double-layer partition 105 or by an additional duct. The second return air duct 305 can be gas-connected to the second filter unit 31, so that the clean gas sent into the transfer area 300 by the second filter unit 31 can enter the second return air space 304 through the mesh plate 303 after passing through the conveyor arm 30, and return to the second filter unit 31 through the second return air duct 305. After being filtered by the second filter unit 31 and restored to clean gas, it re-enters the interior of the transfer area 300, forming a second gas circulation loop to save the amount of clean gas used.

[0031] The transfer area 300 is equipped with at least one second environmental detection element 32 electrically connected to the control unit 80. The second environmental detection element 32 may include at least a temperature and humidity detector, a particulate detector, and / or a hazardous gas detector, for detecting the real-time environmental conditions within the transfer area 300. A material inlet channel 33 is formed between the transfer area 300 and the receiving area 200, which can be selectively opened or closed using at least one door 34 connected to the control unit 80 (e.g., ...). Figure 2 As shown, when there is a need to grab or store photomask A in the aforementioned storage turret 20 within the aforementioned storage area 200, the aforementioned conveying arm 30 can be extended through the feed channel 33 after the door 34 is opened, so as to selectively grab or place photomask A at the relative storage position 21 of the aforementioned storage turret 20.

[0032] The receiving and conveying area 400 is provided with an inlet / outlet port 40 connected to the control unit 80. The inlet / outlet port 40 has a side plate 103 corresponding to the compartment 10 and at least one inlet / outlet gate 41 for receiving and conveying the component container B of the photomask A, such as a photomask conveyor box. Furthermore, the inlet / outlet port 40 is provided with an opening mechanism 42 corresponding to the component container B for opening and closing the component container B. A first opening 43 is formed between the receiving and conveying area 400 and the transfer area 300, which is opened and closed by a first gate 44 connected to the control unit 80. When the component container B is opened, the aforementioned conveying arm 30 can extend through the opened first opening 43 to selectively grab or place the aforementioned photomask A corresponding to the component container B. According to some embodiments, a mesh plate 403 is spaced above the bottom plate 102 in the receiving and conveying area 400, such that a fourth return air space 404 is formed between the mesh plate 403 and the bottom plate 102 (e.g., ...). Figure 5 [As shown]. The fourth return air space 404 can also be connected to the aforementioned second return air space 304, so that the gas in the fourth return air space 404 flows back to the second filter unit 31 for filtration through the second return air space 304, and the second filter unit 31 can also deliver clean gas to the receiving and sending area 400.

[0033] In one embodiment of this invention, a process area 500 is provided, within which a process module 50 electrically connected to a control unit 80 is installed. This process module 50 can be a detection device, a cleaning device, or an electrostatic elimination device, etc. This invention primarily uses a photomask detection and particle removal detection module as its main embodiment. The gas filtration system further includes at least one third filtration unit 51 (e.g., ...) on the top plate 101 of the chamber 10. Figure 1 As shown, it is electrically connected to the control unit 80. The third filter unit 51 can correspond to the process area 500 of the gas communication chamber 10 and deliver clean gas. And as... Figure 5As shown, a mesh plate 503 is spaced above the base plate 102 in the process area 500, forming a third return air space 504 between the mesh plate 503 and the base plate 102. Furthermore, at least one third return air duct 505 is provided around the process area 500 in the third return air space 504. The third return air duct 505 can be formed on the inner wall of the process area 500 by a double-layer partition 105 or by an additional duct. The third return air duct 505 is connected to the third filter unit 51, so that the clean air supplied to the process area 500 by the third filter unit 51 flows through the process module 50, enters the third return air space 504 through the mesh plate 503, and returns to the third filter unit 51 through the third return air duct 505. One feature of this invention is that the clean gas can be filtered by the third filtration unit 51 to remove particles or harmful substances and be restored to clean gas before re-entering the process area 500 to form a third gas circulation loop, thereby saving the amount of clean gas used.

[0034] Furthermore, the process area 500 is equipped with at least one third environmental detection element 52 electrically connected to the control unit 80. The third environmental detection element 52 may include at least a temperature and humidity detector, a particulate detector, and / or a harmful gas detector, for detecting the real-time environmental conditions within the process area 500. In addition, a second opening 53 is provided between the process area 500 and the transfer area 300, which can be selectively opened or closed by at least one second gate 54 connected to the control unit 80. When the second gate 54 is opened, the aforementioned transfer arm 30 extends through the second opening 53 to grasp or place the photomask A on the aforementioned process module 50, so that the process module 50 can perform surface inspection or particulate removal on the photomask A.

[0035] Furthermore, according to certain embodiments, such as Figure 2 , Figure 3 and Figure 5 As shown, the interior of the cabin 10 is further divided into at least one maintenance area 600, which can be an independent space for housing control components or servers. The maintenance area 600 can also selectively communicate with the storage area 200, the transfer area 300, or the process area 500 for maintenance of the internal components of the storage area 200, the transfer area 300, or the process area 500. Furthermore, an electrical module 60 connected to a control unit 80 is provided within one of the maintenance areas 600 within the storage area 200, the transfer area 300, or the process area 500. The electrical module 60 can be used to control the various electronic control components of the storage device 100. The maintenance area 600 has an external maintenance door 62 located on one side panel 103 of the cabin 10 (e.g., ...). Figure 1As shown, an outer maintenance door 62 is provided for maintenance personnel to enter and exit the process area 500. An inner maintenance door (not shown) can be provided on the partition 105 of each maintenance area 600 adjacent to the storage area 200, transfer area 300, or process area 500, allowing maintenance personnel to selectively open the inner maintenance door to enter the corresponding storage area 200, transfer area 300, or process area 500 for maintenance when the outer maintenance door 62 is closed. Additionally, a drive module 61 is provided in one of the maintenance areas 600, which can be used to drive the rotation of the wafer turret 20 in the storage area 200 to reduce the number of components that generate particulates in the storage area 200. Furthermore, a mesh plate 603 is spaced above the base plate 102 in the maintenance area 600, forming a fifth return air space 604 between the mesh plate 603 and the base plate 102 to reduce the deposition of particulate matter and other contaminants inside the maintenance area 600.

[0036] Therefore, as Figure 1 , Figure 2 and Figure 3 As shown, the control unit 80 actuates the first filter unit 22, the second filter unit 31, and the third filter unit 51 of the gas filtration system to deliver clean gas into the corresponding receiving area 200, transfer area 300, and process area 500, respectively. The first environmental detection element 23 in the receiving area 200, the second filter unit 31 in the transfer area 300, and the third environmental detection element 52 in the process area 500 continuously monitor their internal environmental parameters and provide these monitored parameters to the control unit 80. This ensures that the pressure of the first gas circulation loop inside the receiving area 200 is greater than the pressure of the second gas circulation loop inside the transfer area 300, and that the pressure of the third gas circulation loop inside the process area 500 is also greater than the pressure of the second gas circulation loop inside the transfer area 300. Furthermore, the internal air pressure of the transfer area 300 is greater than that of the receiving / transfer area 400. Meanwhile, the internal air pressure of the receiving and conveying area 400 is greater than that of the storage equipment 100, so that the gas can only flow from the receiving area 200 to the transfer area 300 and from the process area 500 to the transfer area 300. The gas in the transfer area 300 can flow to the receiving and conveying area 400, effectively preventing particles or harmful gas ions from entering the transfer area 300 from the receiving and conveying area 400 or the maintenance area 600. Furthermore, it can also prevent particles or harmful gas ions from entering the receiving area 200 or the process area 500 from the transfer area 300, so as to ensure the cleanliness of the receiving area 200 and the process area 500. The storage turret 20 of the receiving area 200 can directly receive the exposed photomask A without the need to use other component containers such as photomask transfer boxes.

[0037] The following describes the control method of the control unit 80 in the semiconductor element storage device 100 of this utility model. The main technical feature is that clean gas is provided at different pressures into the storage area 200, transfer area 300, and receiving / delivering area 400 of the chamber 10. Specifically, the air pressure inside the storage area 200 is greater than that inside the transfer area 300, and the air pressure inside the transfer area 300 is greater than that inside the receiving / delivering area 400, while the air pressure inside the receiving / delivering area 400 is greater than that of the environment in which the chamber 10 is located. If the chamber 10 has a process area 500 that can be selectively connected to the transfer area 300, the air pressure inside the process area 500 is further made greater than that inside the transfer area 300. Furthermore, in some embodiments, the air pressure in the process area 500 is less than that in the storage area 200.

[0038] Based on the above description, the storage device 100 of this utility model can control the air pressure in the storage area 200 and the process area 500 to be greater than that in the transfer area 300, and the internal air pressure in the transfer area 300 to be greater than that in the environment where the storage device 100 is located. This design allows gas to continuously flow from the storage area 200 and the process area 500 to the transfer area 300, and from the transfer area 300 to the receiving and delivery area 400 or the maintenance area 600. This ensures the cleanliness of the storage area 200 and the process area 500 of the storage device 100 and can be effectively monitored and maintained in real time. This allows the storage area 200 of the storage device 100 to be used to directly store semiconductor components, thereby increasing the storage capacity of the storage device 100 while reducing its volume. This further reduces the existing gas filling system and components for filling semiconductor component containers, simplifying the structure of the storage device 100, effectively reducing the generation or accumulation of contaminants inside the storage device 100, and thus reducing the manufacturing and maintenance costs of the storage device.

[0039] The above embodiments are merely illustrative of the implementation of this utility model and to explain its technical features, and are not intended to limit the scope of protection of this utility model. Any changes or equivalent arrangements that can be easily made by those skilled in the art are within the scope of this utility model, and the scope of protection of this utility model shall be determined by the claims.

Claims

1. A storage device for accommodating multiple semiconductor components, characterized in that, The storage facility includes: A storage area for storing the multiple semiconductor components; A transfer area, which is spatially independent of but selectively connected to the storage area, is used to receive one of the plurality of semiconductor elements from the outside to the storage area or to transfer one of the plurality of semiconductor elements from the storage area to the outside. A gas filtration system for providing a clean gas; and A return air system is provided, with the gas connected to the gas filtration system, enabling the clean gas to form a gas circulation loop within the receiving area and the transfer area, respectively.

2. The storage device according to claim 1, characterized in that, It also includes a process area that can be selectively connected to the transfer area for performing a semiconductor process on one of the plurality of semiconductor elements.

3. The storage device according to claim 1, characterized in that, The return air system includes a first return air subsystem located inside the storage area. It has a mesh panel and at least one first return air duct. The mesh panel is located at the bottom of the storage area. The at least one first return air duct is connected to the gas filtration system to enable the clean gas to form a first gas circulation loop inside the storage area.

4. The storage device according to claim 1, characterized in that, The return air system includes a second return air subsystem located inside the transfer zone. It has a mesh panel and at least one second return air duct. The mesh panel is located at the bottom of the transfer zone. The at least one second return air duct is connected to the gas filtration system to enable the clean gas to form a second gas circulation loop inside the transfer zone.

5. The storage device according to claim 2, characterized in that, The return air system includes a third return air subsystem located inside the process area. It has a mesh plate and at least one third return air duct. The mesh plate is located at the bottom of the process area. The at least one third return air duct is connected to the gas filtration system to form a third gas circulation loop inside the process area.

6. The storage device according to claim 3, characterized in that, The gas filtration system includes a first gas filtration unit, with gas connected to the first return air duct to provide the clean gas in the first gas circulation loop within the storage area.

7. The storage device according to claim 4, characterized in that, The gas filtration system includes a second gas filtration unit, and the gas is connected to the second return air duct to provide the clean gas in the second gas circulation loop within the transfer area.

8. The storage device according to claim 5, characterized in that, The gas filtration system includes a third gas filtration unit, and the gas is connected to the third return air duct to provide the clean gas in the third gas circulation loop within the process area.

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