A door cover and a wafer transfer box

Abstract

This application discloses a door cover and a wafer transfer box. The door cover includes a filter assembly to allow external gas to enter the housing cavity of the wafer transfer box after being purified by the filter assembly. In the filter assembly, the base has an air inlet communicating with the outside, and the filter body has a filter channel and a filter inlet and a filter outlet communicating with the filter channel. The filter body is detachably installed on the base, and the filter inlet communicates with the air inlet, while the filter outlet communicates with the housing cavity of the wafer transfer box. The filter element fills the filter channel. The filter element has a porous structure to improve filtration efficiency and achieve balance of the pressure difference between the inside and outside of the wafer transfer box. The base has a first main wall facing the housing cavity, and the air inlet is located on the first main wall. The filter body has a first side wall, and the first side wall has the filter outlet. The first side wall is set at an angle to the first main wall so that the outlet direction of the filter is deviated from the wafer in the housing cavity, thereby effectively preventing the airflow from directly impacting the wafer surface.

Description

Technical Field

[0001] This application relates to the field of semiconductor manufacturing technology, and in particular to a door cover and a wafer transfer box. Background Technology

[0002] In semiconductor manufacturing and packaging, wafer transfer cases are used to hold and transport wafers. To maintain the stability of the internal clean environment, the wafer transfer case door and case body are usually sealed to prevent external air and contaminants from entering the case during storage and handling. However, after undergoing high and low temperature treatments, cleaning, and drying, changes in internal air temperature or humidity can easily create a pressure difference between the inside and outside of the case. This increases the resistance to opening the door, and the sudden release of pressure at the moment of opening can cause the door to spring open violently. This not only poses a safety hazard but may also introduce particle disturbance, allowing external particles to directly impact the wafer surface with the airflow, which is detrimental to dust and cleanliness control. Utility Model Content

[0003] This application provides a door cover and a wafer transfer box, which can solve the problem of balancing the internal and external air pressure difference in the wafer transfer box.

[0004] In a first aspect, embodiments of this application provide a door cover for a wafer transfer box. The door cover includes a filter assembly, which includes a base, a filter body, and a filter element. The base has an air inlet communicating with the outside. The filter body has a filter channel and a filter inlet and a filter outlet communicating with the filter channel. The filter body is detachably installed on the base, and the filter inlet communicates with the air inlet. The filter outlet communicates with the receiving cavity of the wafer transfer box. The filter element fills the filter channel. The base has a first main wall facing the receiving cavity, and the air inlet is located on the first main wall. The filter body has a first side wall, and the first side wall has the filter outlet. The first side wall and the first main wall are arranged at an angle so that the air outlet direction of the filter outlet deviates from the wafer in the receiving cavity. The filter element has a porous structure so that external gas enters the filter inlet from the air inlet, passes through the filter element, and then enters the wafer transfer box from the filter outlet.

[0005] In some embodiments, the filter element is one of a nylon filter element, a Teflon filter element, or a fiber filter element.

[0006] In some embodiments, the area of ​​the flow cross-section of the filter element is S, and the pore size of the filter element is ε; the filter element satisfies at least one of the following conditions:

[0007] (1) 13mm 2 ≤S≤40mm 2;

[0008] (2)0.15µm≤ε≤0.3µm.

[0009] In some embodiments, the door cover includes a cover body and at least one filter assembly, each of the filter assemblies being disposed in a corner area of ​​the cover body;

[0010] In one embodiment, the filter outlet of the filter body is disposed facing the side edge of the cover; or, the filter outlet of the filter body is disposed diagonally away from the center of the cover.

[0011] In some embodiments, the seat includes a surrounding panel, a base plate, and a top plate, wherein the base plate and the top plate are disposed at opposite ends of the surrounding panel along the thickness direction of the door cover, and the base plate has the first main wall surface;

[0012] The filter body includes a first sidewall, which is provided with the filter inlet. The first sidewall is located between the base plate and the top plate, and together with the base plate, the top plate and the surrounding plate, it encloses a buffer channel. One end of the buffer channel is connected to the air inlet and the other end is connected to the filter inlet.

[0013] In some embodiments, the seat includes a base plate, a surrounding plate, and at least one locking part. The base plate is provided with the air inlet, the surrounding plate protrudes from the base plate, and the locking part is connected to at least one of the base plate and the surrounding plate.

[0014] The filter body includes a main housing and at least one mating part connected to the main housing, each of the mating parts engaging with a locking part.

[0015] In some embodiments, the enclosure includes two first enclosure walls connected at an included angle, one of the locking parts is a first locking part, and the seat includes two first locking parts, each of the first locking parts protruding from the wall surface of one of the first enclosure walls;

[0016] One of the mating parts is a first mating part. The filter body includes two first mating parts. Each first mating part is snapped into a first locking part along a direction perpendicular to the thickness direction of the door cover, so that the main housing abuts against the first enclosure wall.

[0017] In some embodiments, the enclosure includes two second enclosure walls connected at an included angle, one of the locking parts is a second locking part, the base includes two second locking parts, each second locking part is connected to the base plate and is disposed opposite to one of the second enclosure walls;

[0018] One of the mating parts is a second mating part. The filter body includes two second mating parts. Each second mating part extends from the main housing in a direction parallel to a second enclosure wall. Each second mating part is engaged with a second locking part along the thickness direction of the door cover and is sandwiched between the second locking part and the corresponding second enclosure wall.

[0019] In some embodiments, one of the mating parts is a third mating part, and the filter body includes the third mating part, which extends from the main housing in a direction parallel to the enclosure.

[0020] One of the locking parts is a third locking part, and the seat body also includes a limiting part, which protrudes from the base plate, and the third locking part is connected to the end of the enclosure plate away from the base plate;

[0021] The main housing is disposed between the limiting part and the enclosure plate along the first direction, and the third locking part is engaged with the third mating part so that the third mating part abuts against the enclosure plate along the second direction. The first direction, the second direction and the thickness direction of the door cover are perpendicular to each other.

[0022] Secondly, this application also provides a wafer transfer box, which includes a box body and a door cover. The door cover is closably mounted on the box body. In the closed state of the door cover relative to the box body, the door cover and the box body together define a receiving cavity for receiving wafers.

[0023] According to an embodiment of this application, a door cover and a wafer transfer box are provided. The door cover is equipped with a filter assembly. External gas is purified by the filter assembly and then enters the receiving cavity of the wafer transfer box. The filter body is filled with a filter element with a porous structure. The porous filter element has a high gas permeability, which can accelerate gas exchange efficiency while meeting the filtration accuracy requirements, that is, improve filtration efficiency, thereby shortening the equalization time of the pressure difference between the inside and outside of the wafer transfer box. In this application, the first side wall with the filter outlet in the filter body is arranged at an angle relative to the first main wall with the air inlet in the seat body. This makes the outlet direction of the clean gas deviate from the wafer position in the receiving cavity, thereby effectively avoiding the airflow directly impacting the wafer surface and suppressing the risk of contamination of the wafer by residual moisture in the airflow. Attached Figure Description

[0024] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0025] Figure 1 This is a partially exploded structural diagram of the door cover of a wafer transfer box in related technologies;

[0026] Figure 2 This is a top view of a door cover according to an embodiment of this application;

[0027] Figure 3 This is a schematic diagram of the structure of a filtering component according to an embodiment of this application;

[0028] Figure 4 for Figure 3 A schematic diagram of the cross-sectional structure along the AA direction;

[0029] Figure 5 This is an exploded structural diagram of a filtering component according to an embodiment of this application;

[0030] Figure 6 This is a schematic diagram of the structure of a filtering component according to another embodiment of this application;

[0031] Figure 7 This is an exploded structural diagram of a filtering component according to another embodiment of this application;

[0032] Figure 8 This is a schematic diagram of the structure of a filtering component according to another embodiment of this application;

[0033] Figure 9 This is an exploded structural diagram of a filtering component according to another embodiment of this application;

[0034] Figure 10 This is a schematic diagram of the structure of a filter body according to an embodiment of this application.

[0035] Figure label:

[0036] 1. Door cover;

[0037] 10. Cover;

[0038] 20. Needle filter;

[0039] 30. Filter assembly; 300. Buffer channel; 31. Seat; 311. Base plate; 301. First main wall surface; 31a. Air inlet; 312. Enclosure; 3121. First enclosure; 3122. Second enclosure; 3123. Third enclosure; 313. Top plate; 314. First locking part; 315. Second locking part; 3151. Second elastic arm; 3152. Second hook; 316. Limiting part; 317. Third locking part; 3171. Fixing arm; 3172. Third elastic arm; 3173. Third hook; 318. Second insertion part;

[0040] 32. Filter body; 320. Filter channel; 302. First side wall; 32a. Filter inlet; 32b. Filter outlet; 321. Main housing; 3211. Air inlet side wall; 322. First mating part; 3221. First hook; 3222. First elastic arm; 323. Second mating part; 324. First insertion part; 325. Third mating part; 326. Third insertion part; 33. Filter element; 34. Baffle;

[0041] X, the thickness direction of the door cover; Y, the first direction; Z, the second direction. Detailed Implementation

[0042] To make the objectives, technical solutions, and advantages of this application clearer, the following detailed description is provided in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the scope of this application.

[0043] In semiconductor manufacturing processes, wafer transfer pods serve as carriers for the storage, transfer, and automated docking of wafers. Among them, FOUP (Front Opening Unified Pod) is widely used in cleanroom wafer handling scenarios due to its strong adaptability to automated equipment and high sealing performance. After the wafer transfer pod undergoes high-temperature drying, low-temperature storage, or cleaning, the internal air conditions are prone to change, resulting in a significant pressure difference between the inside and outside of the pod. If this pressure difference is not released in time when the pod is opened, it can not only obstruct the opening of the pod but may even cause the pod to violently spring open, posing operational risks and potential damage to the wafer.

[0044] like Figure 1 As shown, in related technologies, some wafer transfer cases use a needle filter 20 on the cover 10 of the door cover 1 to filter external air particles before it enters the case, thereby alleviating pressure differences while ensuring cleanliness. However, the needle filter has low filtration efficiency when meeting high cleanliness requirements (e.g., blocking particles with a diameter ≥0.45μm), and it often takes a long time to achieve internal and external pressure balance. Based on this, this application provides a door cover and a wafer transfer case that can meet both the requirements of pressure balance and high-efficiency cleanliness.

[0045] Please see Figure 2 This application provides a door cover 1 for a wafer transfer box. The door cover 1 includes a filter assembly 30, such as... Figures 3-4As shown, the filter assembly 30 includes a base 31, a filter body 32, and a filter element 33. The base 31 has an air inlet 31a communicating with the outside. The filter body 32 has a filter channel 320 and a filter inlet 32a and a filter outlet 32b communicating with the filter channel 320. The filter body 32 is detachably installed on the base 31, and the filter inlet 32a communicates with the air inlet 31a. The filter outlet 32b communicates with the receiving cavity of the wafer transfer box. The filter element 33 fills the filter channel 320. When there is a pressure difference between the inside and outside of the wafer transfer box, for example, when the pressure inside the wafer transfer box is lower, the external gas is driven by the pressure difference to enter the filter inlet 32a from the air inlet 31a, is filtered by the filter element 33, and then enters the wafer transfer box from the filter outlet 32b. In this way, the pressure difference between the inside and outside of the wafer transfer box is balanced, while suppressing particles mixed in the external gas from entering the wafer transfer box. Among them, filter element 33 has a porous structure, high gas permeability, and good filtration effect and efficiency. It can increase gas flow rate, meet the filtration accuracy requirements, and accelerate gas exchange efficiency, thereby achieving internal and external air pressure balance in a short time.

[0046] When the flow rate of clean gas entering the wafer transfer box is large, more water vapor is mixed in with the gas and enters the wafer transfer box. To suppress the condensation and contamination of the wafer by water vapor, this application designs the first side wall 302 where the filter outlet 32b is located so that the outlet direction of the filter outlet 32b is deviated from the wafer, thereby reducing the impact and adhesion of water vapor on the wafer surface. Specifically, the base 31 has a first main wall 301 facing the accommodating cavity, and the air inlet 31a is located on the first main wall 301. The filter body 32 has a first side wall 302, and the first side wall 302 is provided with the filter outlet 32b. The first side wall 302 is set at an angle to the first main wall 301 so that the outlet direction of the filter outlet 32b is deviated from the wafer in the accommodating cavity. The porous filter element 33 has high filtration efficiency and can effectively compensate for the slowdown in flow rate caused by airflow deflection, allowing for a deflected airflow path within the filter assembly 30.

[0047] Optionally, filter element 33 can be one of nylon, Teflon, or fiber filter elements. For example, filter element 33 can be a fiber filter element, in which the fiber material has a three-dimensional stacked structure with small pore size and high porosity, facilitating airflow passage and particle interception to achieve high-efficiency filtration. When particles move with the airflow to the fiber surface, if the particle radius is greater than the distance from the particle center to the limiting surface, the particles will be intercepted on the fiber surface due to van der Waals forces. Furthermore, the fiber material has a high specific surface area and microporous channels. During the movement of suspended particles in the gas with the airflow, the particles come into contact with the fiber material and are filtered due to inertial collisions and gravitational settling. Simultaneously, the fiber material has low flow resistance, allowing clean gas to quickly penetrate the filter medium, enabling the fiber filter element to achieve high-efficiency filtration and rapidly balance the air pressure inside and outside the wafer transfer box. As another example, filter element 33 can be a Teflon filter element, in which the Teflon material has a dense and uniform microporous structure, meeting the high cleanliness requirements of semiconductor manufacturing processes.

[0048] In some embodiments, the area of ​​the flow cross section of the filter element 33 is S, where S satisfies: 13 mm² 2 ≤S≤40mm 2 The airflow direction within the filter channel 320 of the filter body 32 is as follows: Figure 4 As shown, the flow cross-section of filter element 33 refers to the cross-section of filter element 33 perpendicular to the gas flow direction. Optionally, the flow cross-section of filter element 33 can be set as circular, rectangular, or other feasible shapes, and the cavity shape of filter channel 320 is adapted to the outer contour of filter element 33. This application controls the area S of the flow cross-section to meet the above range, so that the filter assembly 30 can provide the necessary filtration effect while achieving an appropriate gas throughput to meet the requirements of the wafer transfer box for internal and external gas pressure balance. S≥13mm 2 Excessive gas exchange between the wafer transfer box and the external environment can easily cause fluctuations in temperature and humidity within the box, potentially leading to a decrease in cleanliness. S≤40mm 2 The limited airflow capacity of filter element 33 results in a prolonged pressure equalization time.

[0049] In some embodiments, the filter pore size of filter element 33 is ε, which satisfies: 0.15µm≤ε≤0.3µm. For example, the value of ε can be 0.15µm, 0.2µm, 0.3µm or any range of the above two. By controlling the filter pore size ε to meet the above range, the cleanliness requirements of the wafer transfer box are met, while also taking into account the filtration efficiency.

[0050] In this embodiment, the cover 1 includes a cover body 10 and at least one filter assembly 30. The filter assembly 30 is disposed on the cover body 10. The base 31 of the filter assembly 30 and the cover body 10 are integrally formed, or the base 31 of the filter assembly 30 is separately disposed from the cover body 10 and detachably installed on the cover body 10. In actual manufacturing, both the base 31 and the filter body 32 are made of PE (Polyethylene) material. PE material has good flexibility and low hardness, which can reduce scratches caused by relative movement between the base 31 and the filter body 32 during assembly or operation, reducing the risk of particle generation and thus maintaining the cleanliness inside the wafer transfer box. Depending on structural strength and process compatibility, the cover 10 is made of PE material or PP (Polypropylene) material.

[0051] In some embodiments, each filter assembly 30 is disposed in a corner area of ​​the cover 10, and the filter assembly 30 is arranged in a region away from the wafer in the accommodating cavity to reduce the risk of water vapor in the clean gas contaminating or even corroding the wafer.

[0052] In some embodiments, the filter outlet 32b of the filter body 32 is disposed facing one side edge of the cover 10 to guide clean gas to diffuse along the edge of the cover 10, reducing the risk of water vapor entrained in the clean gas contaminating or even corroding the wafer. For example, the cover 1 includes a filter assembly 30, in which the filter outlet 32b of the filter body 32 is disposed facing one side edge of the cover 10. Or, for example, the cover 1 includes multiple filter assemblies 30, in which the filter outlet 32b of the filter body 32 of each of the multiple filter assemblies 30 is disposed facing one side edge of the cover 10.

[0053] In some embodiments, the filter outlet 32b of the filter body 32 is arranged diagonally away from the center of the cover 10 along the opposite direction of the cover 10, so as to guide the clean gas to flow around the periphery of the cover 10 and reduce the risk of water vapor entrained in the clean gas contaminating or even corroding the wafer. Here, the center of the cover 10 refers to the geometric center of the cover 10. For example, the door cover 1 includes a filter assembly 30, in which the filter outlet 32b of the filter body 32 is arranged diagonally away from the center of the cover 10. Or, for example, the door cover 1 includes multiple filter assemblies 30, in which the filter outlet 32b of the filter body 32 of the multiple filter assemblies 30 is arranged diagonally away from the center of the cover 10.

[0054] Optionally, the cover 1 includes multiple filter assemblies 30, wherein the filter outlets 32b of the filter body 32 in some filter assemblies 30 are respectively arranged facing one side edge of the cover 10, and the filter outlets 32b of the filter body 32 in other filter assemblies 30 are all arranged diagonally away from the center of the cover 10, which can also reduce the risk of water vapor in the clean gas contaminating or even corroding the wafer.

[0055] In this embodiment, the base 31 includes a base plate 311, a surrounding plate 312, and at least one locking part. The base plate 311 has an air inlet 31a, the surrounding plate 312 protrudes from the base plate 311, and the locking part is connected to at least one of the base plate 311 and the surrounding plate 312. For example, the locking part is connected to the base plate 311, or the locking part is connected to the surrounding plate 312, or a portion of the locking part is connected to the base plate 311 and a portion is connected to the surrounding plate 312. The filter body 32 includes a main housing 321 and at least one mating part connected to the main housing 321.

[0056] The base plate 311 and the surrounding plate 312 provide an installation foundation for the filter body 32. Each mating part engages with a locking part to achieve assembly between the base 31 and the filter body 32 and to lock the position of the filter body 32. The snap-fit ​​connection is stable and the assembly efficiency is high. The main housing 321 abuts against the surrounding plate 312, and the connection between the main housing 321 and the surrounding plate 312 is sealed and fitted to prevent external gas from bypassing the filter element 33 and directly entering the wafer transfer box, which helps maintain the cleanliness of the receiving cavity.

[0057] The structure of the filter component 30 in this application will now be described in conjunction with the accompanying drawings and specific embodiments.

[0058] Please see Figures 4-5 One type of mating part is a first mating part 322. The filter body 32 includes two first mating parts 322. The first mating parts 322 are connected to the outer wall of the main housing 321. The enclosure 312 includes two first enclosure walls 3121 connected at an angle. One type of locking part is a first locking part 314. The seat 31 includes two first locking parts 314. Each first locking part 314 protrudes from the wall of a first enclosure wall 3121. Each first mating part 322 is engaged with a first locking part 314 in a direction perpendicular to the thickness direction X of the door cover 1, so that the main housing 321 presses against the first enclosure wall 3121.

[0059] In the snap-fit ​​structure of the filter assembly 30 described above, the main housing 321 is pushed towards the inside of the angle between the two first enclosure walls 3121, and is simultaneously restricted in two orthogonal directions to prevent the filter body 32 from loosening, shifting, or rotating after assembly. Of course, the two first enclosure walls 3121 can be arranged perpendicularly to each other to apply a restraining force to the filter body 32 in their respective normal directions. Alternatively, the two first enclosure walls 3121 can be arranged at a non-perpendicular angle; in the snap-fit ​​state, the first enclosure walls 3121 apply a clamping force to the main housing 321 along their respective normal directions. These two normal directions can still be decomposed into two mutually orthogonal components in space, thus achieving the limitation of the main housing 321 in two orthogonal directions. Simultaneously, the snap-fit ​​position of the base 31 and the filter body 32 is close to the first enclosure wall 3121, resulting in a compact structure for the filter assembly 30 that does not occupy additional installation space on the cover 10.

[0060] In some embodiments, the first mating part 322 includes a first hook 3221 and a first elastic arm 3222. The two ends of the first elastic arm 3222 are respectively connected to the main housing 321 and the first hook 3221. The first elastic arm 3222 can elastically deform in a direction perpendicular to the snapping direction to drive the first hook 3221 to move away from or towards the corresponding first locking part 314. During installation, the first hook 3221 deflects under the action of the first elastic arm 3222, thereby passing over the first locking part 314 and elastically resetting on its back side, achieving reliable snapping. During disassembly, simply pressing or pulling the first elastic arm 3222 disengages the first hook 3221 from the first locking part 314 to release the lock.

[0061] In some embodiments, the seat 31 includes a surrounding plate 312, a base plate 311, and a top plate 313. The base plate 311 and the top plate 313 are respectively disposed at opposite ends of the surrounding plate 312 along the thickness direction X of the door cover 1. The base plate 311 has a first main wall surface 301. The filter body 32 includes an air inlet side wall 3211. The air inlet side wall 3211 is provided with a filter inlet 32a. The air inlet side wall 3211 is located between the base plate 311 and the top plate 313. When the filter body 32 is installed on the seat 31, the air inlet side wall 3211, the base plate 311, the top plate 313, and the surrounding plate 312 together enclose a buffer channel 300. One end of the buffer channel 300 is connected to the air inlet 31a, and the other end is connected to the filter inlet 32a. The air inlet 31a and the filter inlet 32a can be connected without the need for an additional docking structure. The assembly of the seat 31 and the filter body 32 is more convenient, which helps to simplify the overall structure of the filter assembly 30 and reduce manufacturing costs.

[0062] It should be noted that when the seat 31 includes a top seat plate 313 disposed opposite to the base plate 311, the first main wall surface 301 is located on the side wall of the base plate 311 facing the receiving cavity.

[0063] Please see Figures 6-7 In some embodiments, the filter body 32 is mounted on the base 31 along the thickness direction X of the cover 1. The enclosure 312 includes two second enclosure walls 3122 connected at an angle, and one of the locking parts is a second locking part 315. The base 31 includes two second locking parts 315, each of which is connected to the base plate 311 and is disposed opposite to one of the second enclosure walls 3122. One type of mating part is a second mating part 323. The filter body 32 includes two second mating parts 323. Each second mating part 323 extends from its own housing 321 in a direction parallel to a second enclosure wall 3122. That is, one end of the housing 321 of one second mating part 323 extends in a direction parallel to one second enclosure wall 3122, and the other end of the housing 321 of the other second mating part 323 extends in a direction parallel to the other second enclosure wall 3122. Each second mating part 323 is engaged with a second locking part 315 along the thickness direction X of the door cover 1, and the second mating part 323 is sandwiched between the second locking part 315 and the corresponding second enclosure wall 3122.

[0064] In the snap-fit ​​structure of the filter assembly 30 described above, in a plane perpendicular to the thickness direction X of the cover 1, each second locking part 315 and its opposite second enclosure wall 3122 laterally limit the second mating part 323, preventing lateral displacement or rotation of the second mating part 323, thereby limiting the filter body in two orthogonal directions. The two second enclosure walls 3122 can be arranged perpendicularly to each other, or they can be arranged at a non-perpendicular angle. The second locking part 315 and the two second enclosure walls 3122 are integrally formed on the base plate 311. During installation, simply pushing the filter body 32 along the thickness direction X completes the snap-fit ​​and clamping, eliminating the need for additional fasteners and reducing assembly difficulty and time costs.

[0065] In some embodiments, the second locking part 315 includes a second elastic arm 3151 and a second hook 3152. The second elastic arm 3151 extends along the thickness direction X of the door cover 1, and its two ends are respectively connected to the base plate 311 and the second hook 3152. During the installation of the filter body 32, the second elastic arm 3151 undergoes elastic deformation so that the second mating part 323 can extend into the space between the second locking part 315 and the second enclosure 3122. After the filter body 32 is installed in place, the second elastic arm 3151 elastically resets and drives the second hook 3152 to lock the second mating part 323. The second elastic arm 3151 continuously provides clamping force so that the seat 31 and the filter body 32 maintain a stable locking state.

[0066] Please continue reading. Figures 6-7The filter body 32 also includes a first insertion part 324 connected to the main housing 321. The first insertion part 324 is provided with a first air passage. The first insertion part 324 is inserted into the air inlet 31a of the base plate 311. The two ends of the first air passage are respectively connected to the air inlet 31a and the filter inlet 32a, so as to realize the alignment and connection of the air inlet 31a and the filter inlet 32a.

[0067] Please see Figures 8-9 In some embodiments, the filter body 32 is mounted on the base 31 along a direction perpendicular to the thickness direction X of the cover 1. One type of mating part is a third mating part 325. The filter body 32 includes the third mating part 325, which extends from one end of the main housing 321 along a direction parallel to the surrounding plate 312. The base 31 also includes a limiting part 316, which protrudes from the base plate 311. One type of locking part is a third locking part 317, which is connected to the end of the surrounding plate 312 away from the base plate 311. The filter body 32 is inserted into the base 31 along the extending direction of the limiting part 316. The main housing 321 is disposed between the limiting part 316 and the surrounding plate 312 along the first direction Y. The third locking part 317 engages with the third mating part 325 so that the third mating part 325 abuts against the surrounding plate 312 along the second direction Y. The first direction Y, the second direction, and the thickness direction X of the cover 1 are all perpendicular to each other. In this way, the filter body 32 is constrained in three mutually perpendicular directions, effectively preventing displacement, loosening or vibration during use.

[0068] In some embodiments, the enclosure 312 includes two third enclosure walls 3123 connected at an included angle. The third locking part 317 includes a fixing arm 3171, a third elastic arm 3172, and a third hook 3173. The fixing arm 3171 extends from one third enclosure wall 3123 to the other third enclosure wall 3123. The third elastic arm 3172 is arranged along the second direction Y, and its two ends are respectively connected to the fixing arm 3171 and the third hook 3173. During the installation of the filter body 32, the third elastic arm 3172 undergoes elastic deformation and drives the third hook 3173 to move away from the base plate 311. After the filter body 32 is installed in place, the third elastic arm 3172 elastically resets so that the third mating part 325 engages between the third hook 3173 and the third enclosure wall 3123, thereby achieving a stable engagement between the filter body 32 and the base 31.

[0069] Please see Figures 9-10The base 31 also includes a second insertion portion 318 protruding from the base plate 311. The second insertion portion 318 has a second air passage that connects to the air inlet 31a and extends at least partially along the second direction Z. The filter body 32 also includes a third insertion portion 326 connected to the main housing 321. The third insertion portion 326 has a third air passage that connects to the filter inlet 32a. The second insertion portion and the third insertion portion 326 are inserted into each other along the second direction Z, and the third air passage connects to the second air passage, thereby connecting the air inlet 31a and the filter inlet 32a.

[0070] The main housing 321 has a recessed area corresponding to the position of the second insertion part 318, and the third insertion part 326 is provided in the recessed area of ​​the main housing 321. The second insertion part 318 is accommodated in the recessed area of ​​the main housing 321 and is inserted and engaged with the third insertion part 326, thereby reducing the size of the filter assembly 30 along the second direction Z.

[0071] In this embodiment, the filter assembly 30 further includes a baffle 34, which is installed on the wall of the filter body 32 to define the filter outlet 32a. The baffle 34 has a vent communicating with the filter outlet 32a. For example, the baffle 34 can be a grid plate with multiple spaced vents to allow the clean gas filtered by the filter element 33 to flow smoothly. The baffle 34 supports and fixes the filter element 33, preventing the filter element 33 from moving relative to the filter body 32.

[0072] This application also provides a wafer transfer box, which includes a box body and a cover 1. The cover 1 is closable and mounted on the box body. When the cover 1 is closed relative to the box body, the cover 1 and the box body together define a receiving cavity for accommodating wafers. In actual use, gas is filtered by a filter assembly 30 before entering or exiting the wafer transfer box, ensuring that the internal and external air pressure of the wafer transfer box is balanced, maintaining the cleanliness and stability of the receiving cavity, and ensuring the safe storage and transfer of wafers.

[0073] In the accompanying drawings of this embodiment, the same or similar reference numerals correspond to the same or similar components. In the description of this application, it should be understood that if terms such as "upper," "lower," "left," and "right" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, they are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, the terms used to describe positional relationships in the accompanying drawings are only for illustrative purposes and should not be construed as limiting this patent. For those skilled in the art, the specific meaning of the above terms can be understood according to the specific circumstances.

[0074] The above description is merely a preferred embodiment of this application and is not intended to limit this application. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of this application should be included within the protection scope of this application.

Claims

1. A door cover for a wafer transfer cassette, comprising: The door cover includes a filter assembly, the filter assembly comprising: The base has an air intake that communicates with the outside; A filter body has a filter channel and a filter inlet and a filter outlet communicating with the filter channel. The filter body is detachably mounted on the base, and the filter inlet communicates with the air inlet, while the filter outlet communicates with the receiving cavity of the wafer transfer box. Filter element, filled into the filter channel; The base has a first main wall facing the accommodating cavity, the air inlet is located on the first main wall, the filter body has a first side wall, the first side wall has the filter outlet, the first side wall is set at an angle to the first main wall so that the air outlet direction of the filter outlet deviates from the wafer in the accommodating cavity, and the filter element has a porous structure so that external gas enters the filter inlet from the air inlet, passes through the filter element, and enters the wafer transfer box from the filter outlet.

2. The door cover according to claim 1, characterized in that The filter element is one of nylon filter element, Teflon filter element, or fiber filter element.

3. The door cover according to claim 2, characterized in that In the direction perpendicular to the gas flow direction, the area of ​​the flow cross section of the filter element is S, and the pore size of the filter element is ε. The filter element satisfies at least one of the following conditions: (1) 13 mm 2 ≤ S ≤ 40 mm 2 ; (2)0.15µm≤ε≤0.3µm.

4. The door cover according to claim 1, characterized in that, The door cover includes a cover body and at least one filter assembly, with each filter assembly correspondingly disposed in a corner area of ​​the cover body; The filter outlet of the filter body is disposed facing the side edge of the cover, or the filter outlet of the filter body is disposed diagonally away from the center of the cover.

5. The door cover according to claim 1, characterized in that, The seat body includes a surrounding panel, a base plate, and a top plate. The base plate and the top plate are respectively disposed at opposite ends of the surrounding panel along the thickness direction of the door cover. The base plate has the first main wall surface. The filter body includes a first sidewall, which is provided with the filter inlet. The first sidewall is located between the base plate and the top plate, and together with the base plate, the top plate and the surrounding plate, it encloses a buffer channel. One end of the buffer channel is connected to the air inlet and the other end is connected to the filter inlet.

6. The door cover of claim 1, wherein The seat includes a base plate, a surrounding plate, and at least one locking part. The base plate is provided with the air inlet, the surrounding plate protrudes from the base plate, and the locking part is connected to at least one of the base plate and the surrounding plate. The filter body includes a main housing and at least one mating part connected to the main housing, each of the mating parts engaging with a locking part.

7. The door cover according to claim 6, characterized in that, The enclosure includes two first enclosure walls connected at an angle, and one of the locking parts is a first locking part. The seat includes two first locking parts, and each first locking part protrudes from the wall surface of one of the first enclosure walls. One of the mating parts is a first mating part. The filter body includes two first mating parts. Each first mating part is snapped into a first locking part along a direction perpendicular to the thickness direction of the door cover, so that the main housing abuts against the first enclosure wall.

8. The door cover according to claim 6, characterized in that, The enclosure includes two second enclosure walls connected at an angle, and one of the locking parts is a second locking part. The base includes two second locking parts, each of which is connected to the base plate and is disposed opposite to one of the second enclosure walls. One of the mating parts is a second mating part. The filter body includes two second mating parts. Each second mating part extends from the main housing in a direction parallel to a second enclosure wall. Each second mating part is engaged with a second locking part along the thickness direction of the door cover and is sandwiched between the second locking part and the corresponding second enclosure wall.

9. The door cover according to claim 6, characterized in that, One of the mating parts is a third mating part, and the filter body includes a third mating part, which extends from the main housing in a direction parallel to the enclosure. One of the locking parts is a third locking part, and the seat body also includes a limiting part, which protrudes from the base plate, and the third locking part is connected to the end of the enclosure plate away from the base plate; The main housing is disposed between the limiting part and the enclosure plate along the first direction, and the third locking part is engaged with the third mating part so that the third mating part abuts against the enclosure plate along the second direction. The first direction, the second direction and the thickness direction of the door cover are perpendicular to each other.

10. A wafer transfer cassette, characterized by, include: Box body; and The cover according to any one of claims 1-9, wherein the cover is closably mounted on the housing, and in the closed state of the cover relative to the housing, the cover and the housing together define a receiving cavity for receiving a wafer.

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