Air curtain device for wafer cases

Abstract

The air curtain device for the wafer case has a casing, the casing has an internal space, the internal space is defined into a lateral gas space, a curved gas space and a vertical gas space, at least one first gas guide plate is provided in the lateral gas space and / or the curved gas space, the first gas guide plate has a plurality of first gas guide holes, and a second gas guide plate is provided in the vertical gas space, the second gas guide plate has a plurality of second gas guide holes.

Description

[Technical field]

[0001] The present invention relates to a wafer case, and more particularly to an air curtain device for a wafer case. [Background technology]

[0002] A wafer case (Front Opening Unified Pod: FOUP) is a container used in semiconductor manufacturing processes to protect, transport and store wafers, and its most important function is to prevent the wafers inside from being contaminated by particles and moisture from the external environment while being transported between different production equipment. When the wafer case is transported to the wafer case load port connected to the equipment front end module (EFEM) of the equipment and the front door of the wafer case is opened in preparation for the manufacturing process, the air curtain device installed above the wafer case load port door in the EFEM blows clean, dry air downward to form an invisible wall that blocks the opening of the case, preventing particles and moisture from inside the EFEM from entering the case while the wafer is being transported to the manufacturing process space.

[0003] Wafers have very high requirements for low levels of particle contamination and moisture in the environment, and if the above-mentioned air curtain device does not emit a laminar flow in a straight line but emits a turbulent flow with a disturbed flow direction, particles outside the case and gas containing high moisture will be entrained into the case, causing contamination and defeating the original purpose of preventing particles and moisture from entering the wafer case (FOUP).

[0004] Conventional air curtain devices have an air hole at the top that is connected to the inside of the air curtain device, and a horizontal, elongated space inside. Air is transported through the air hole to the space of the air curtain device to form an airflow. The space has a plurality of air vents arranged vertically at intervals, and when the airflow is ejected through these air vents, an air curtain is formed. However, after the airflow enters the space, it is quickly ejected from these air vents, and regardless of the structural arrangement, the ejected airflow is guided to a linear laminar flow. When the airflow is ejected radially through these air vents, the airflows interfere with each other and the flow direction is disturbed, and the flow direction formed after the airflow is ejected is disturbed and a turbulent flow is formed, which is a drawback of the device. This causes particles and gas containing a large amount of moisture in the EFEM to be caught up in the wafer case. Summary of the Invention

[0005] The main objective of the present invention is to provide an air curtain device for a wafer case that blows clean, dry gas in a manner that approximates laminar flow, minimizes the reduction in turbulence formation, and prevents moisture and particles in the gas flowing within the EFEM from being entrained in the wafer case.

[0006] In order to achieve the above-mentioned object, the present invention provides an air curtain device for a wafer case, which comprises a casing, at least one first gas guide plate and a second gas guide plate. The casing has an interior space, and a cross-section of the casing defines the interior space into a lateral gas space, a curved gas space communicating with the lateral gas space, and a vertical gas space communicating with the curved gas space, and the casing has at least one intake port communicating with the lateral gas space and an exhaust port communicating with the vertical gas space. At least one first gas guide plate is provided in the lateral gas space and / or in the curved gas space, the first gas guide plate having a plurality of first gas guide holes. The second gas guide plate is provided at one end of the vertical gas space adjacent to the exhaust port, and the second gas guide plate has a plurality of second gas guide holes. The number of the second gas guide holes is greater than the number of the first gas guide holes, and the total area of ​​each of the second gas guide holes on the second gas guide plate is greater than the total area of ​​each of the first gas guide holes on the first gas guide plate.

[0007] Preferably, the cross-sectional diameter of the end of the vertical gas space is larger than the cross-sectional diameter of the lateral gas space and the cross-sectional diameter of the curved gas space.

[0008] Preferably, the cross-sectional diameter of the curved gas spaces is larger than the cross-sectional diameter of the lateral gas spaces, and the cross-sectional diameter of the ends of the vertical gas spaces is larger than the cross-sectional diameter of the curved gas spaces.

[0009] Preferably, the number of the first gas guide plates is three, one of which is installed in the lateral gas space and the remaining two first gas guide plates are installed in the curved gas space.

[0010] Preferably, the curved gas space is formed in a downward arc, and one of the remaining two first gas guide plates is installed at one horizontal end of the curved gas space, and the other is installed at one vertical end of the curved gas space.

[0011] Preferably, each of the first gas guide plate and the second gas guide plate has an interchangeable structure, and the flow rate and uniformity of the gas flow passing through the first gas guide plate and the second gas guide plate can be adjusted by changing the number and total area of ​​the first gas guide holes and the second gas guide holes.

[0012] Preferably, the first gas guide holes are distributed evenly or non-uniformly in the first gas guide plate to adjust the effect of the air flow passing through.

[0013] Preferably, the casing is comprised of a left plate member, a right plate member and a plurality of separation plates.

[0014] In another embodiment, the casing is formed by joining a left casing and a right casing together.

[0015] In yet another embodiment, the casing is integrally molded. (Implementation method)

[0016] As shown in Figures 1 to 6, this is a first embodiment of an air curtain device for a wafer case provided by the present invention, which is composed of a casing 1, at least one first gas guide plate 2, and a second gas guide plate 3.

[0017] The casing 1 is configured by combining a left plate member 11, a right plate member 12, and multiple separation plates 13 with a front plate member 14 and a rear plate member 15. The casing 1 encloses an internal space 16. The air curtain is installed above the door of the wafer case load port 7 in the Equipment Front End Modules (EFEM).

[0018] As shown in FIG. 3, the cross section of the casing 1 divides the internal space 16 into a horizontal gas space 161, a curved gas space 162 communicating with the horizontal gas space 161, and a vertical gas space 163 communicating with the curved gas space 162. The diameter of the cross section of the end of the vertical gas space 163 is larger than the diameter of the cross section of the horizontal gas space 161 and the diameter of the cross section of the curved gas space 162. In this embodiment, the diameter D2 of the cross section of the curved gas space 162 is larger than the diameter D1 of the cross section of the horizontal gas space 161. The diameter D3 of the cross section of the end of the vertical gas space 163 is larger than the diameter D2 of the cross section of the curved gas space 162. The top surface of the left plate member 11 of the casing 1 has two intake ports 17 communicating with the horizontal gas space 161. The bottom end of the casing 1 has an exhaust port 18 communicating with the vertical gas space 163.

[0019] The first gas guide plate 2 is provided in the lateral gas space 161 and / or the curved gas space 162. The first gas guide plate 2 has a plurality of first gas guide holes 21. In this embodiment, the number of the first gas guide plates 2 is three, and one of the first gas guide plates 2 is provided in one of the separation plates 13 and located in the lateral gas space 161. The remaining two first gas guide plates 2 are located in the curved gas space 162. The curved gas space 162 is formed in a downward arc shape. One of the remaining two first gas guide plates 2 is located at one end of the curved gas space 162 in the horizontal direction, and the other is located at one end of the curved gas space 162 in the vertical direction. In this first embodiment, the remaining two first gas guide plates 2 are of an interchangeable structure.

[0020] The second gas guide plate 3 is provided at one end adjacent to the exhaust port 18 of the vertical gas space 163. The second gas guide plate 3 has a plurality of second gas guide holes 31 formed vertically. Each second gas guide hole 31 has a circular shape and is a replaceable structure.

[0021] As shown in Fig. 4, the number of first gas guide plates 2 is three, and the internal space 16 is divided into at least a first gas space 51, a second gas space 52, a third gas space 53, and a fourth gas space 54. The first gas space 51 communicates with the intake port 17. The fourth gas space 54 communicates with the exhaust port 18. Depending on the shape of each separation plate 13, the first gas space 51, the second gas space 52, and the third gas space 53 are located at the same height and horizontally adjacent to each other, and the fourth gas space 54 is adjacent to the lower side of the third gas space 53.

[0022] Furthermore, the two first gas guide plates 2 are disposed opposite each other, and the first gas space 51 communicates with the second gas space 52 in the horizontal direction via the first gas guide holes 21 that penetrate both plates horizontally, and similarly the second gas space 52 communicates with the third gas space 53 in the horizontal direction. The other first gas guide plate 2 is disposed opposite the second gas guide plate 3, and based on the shape of the curved gas space 162, the third gas space 53 also has a downward arc shape, and the third gas space 53 communicates with the fourth gas space 54 in the vertical direction via the first gas guide holes 21 that penetrate the other first gas guide plate 2 vertically.

[0023] In this embodiment, the first gas guide hole 21 that separates the first gas space 51 and the second gas space 52 has a circular hole shape. The first gas guide hole 21 of the first gas guide plate 2 has a lattice shape. The lattice-shaped gas guide hole mentioned above refers to a plurality of gas guide holes arranged at intervals, and each gas guide hole is formed in an elongated shape extending vertically. Therefore, when the airflow passes through the lattice-shaped first gas guide hole 21, a straightening effect is generated, and the airflow flows in a linear direction. The three first gas guide holes 21 may have a circular or lattice shape, but the present invention is not limited to this.

[0024] 5, the number of second gas guide holes 31 provided by the present invention is greater than the number of first gas guide holes 21, and the total area of ​​each second gas guide hole 31 on the second gas guide plate 3 is greater than the total area of ​​each first gas guide hole 21 on the first gas guide plate 2. The number and total area of ​​each first gas guide hole 21 and each second gas guide hole 31 described above are such that, compared to a single first gas guide plate 2 and second gas guide plate 3, the fewer the number of gas guide holes and the smaller the total area formed on the gas guide plate, the faster the flow rate of the airflow and the lower the uniformity. Conversely, the more the number of gas guide holes and the larger the total area formed on the gas guide plate, the slower the flow rate of the airflow and the higher the uniformity. Therefore, the flow speed of the air flowing through the first gas guide plate 2 is high, and the uniformity of the air flowing through the second gas guide plate 3 is high. The first gas guide plate 2 and the second gas guide plate 3 have a replaceable structure, and by changing the number and total area of ​​the first gas guide holes 21 and the second gas guide holes 31, the flow speed and uniformity of the air flow passing through the first gas guide plate 2 and the second gas guide plate 3 can be adjusted.

[0025] In addition, the second gas guide holes 31 are uniformly distributed in the second gas guide plate 3. The first gas guide holes 21 are uniformly or non-uniformly distributed in the first gas guide plate 2, and similarly, according to the replaceable structure of the first gas guide plate 2, the first gas guide holes 21 can be uniformly distributed in the first gas guide plate 2 or non-uniformly distributed and concentrated at a specific position of the first gas guide plate 2, so as to adjust the effect of the air flow passing through the internal space 16.

[0026] Additionally, an intake pipe 6 is connected to each of the two intake ports 17 of the casing 1. Each intake pipe 6 is perforated at its upper end to introduce clean, dry gas, and has an outlet 61 at its lower end. Each intake pipe 6 extends from its outlet 61 into the intake port 17, and each outlet 61 communicates with the first gas space 51.

[0027] It is particularly noted here that the cross-sectional diameter D2 of the curved gas space 162 is larger than the cross-sectional diameter D1 of the horizontal gas space 161, and the cross-sectional diameter D3 of the vertical gas space 163 is larger than the cross-sectional diameter D2 of the curved gas space 162, and the gas flows through the gas spaces with gradually larger cross-sectional diameters in sequence, thereby reducing the flow rate of the airflow when the gas is sent to the internal space 16. Compared with a straight gas space, the curved gas space 162 allows the airflow to stay in the internal space 16 for a longer period of time, and the cross-sectional diameters are combined with the curved gas space 162 to provide different flow rates and uniformities when the airflow flows through each of the first gas guide plate 2 and the second gas guide plate 3 in the internal space 16. For example, in this embodiment, the airflow has a high flow rate through the first gas guide hole 21, but the flow rate slows down in the curved gas space 162, and when the airflow passes through the second gas guide hole 31, an airflow with an appropriate speed and high uniformity is generated.

[0028] In the above-mentioned structure of the present invention, when gas is introduced into the casing 1 through the intake pipe 6, the gas is first injected into the first gas space 51 from each outlet 61 to form an airflow, as shown in Fig. 6. The airflow in the first gas space 51 is injected into the second gas space 52 through the circular first gas guide holes 21, and when passing through the circular first gas guide holes 21, the flow speed of the airflow becomes faster because the number of the circular first gas guide holes 21 is smaller and the total area on the gas guide plate is smaller.

[0029] Next, when air is injected into the third gas space 53 through one of the lattice-shaped first gas guide holes 21, the airflow is straightened to flow in a horizontal direction because the first gas guide hole 21 is lattice-shaped. Then, the accelerated airflow curves downward along the shape of the third gas space 53, slowing down, and after being straightened for a certain period of time to increase uniformity, the airflow is injected into the fourth gas space 54 through another lattice-shaped first gas guide hole 21, where the airflow is straightened to flow in a linear downward direction.

[0030] Thereafter, when the airflow passes through the second gas guide hole 31 adjacent to the exhaust port 18, the number and total area of ​​each of the second gas guide holes 31 distributed on the second gas guide plate 3 are large, so that when the airflow passes through the second gas guide holes 31, the uniformity of the airflow is increased and the straightened airflow flows uniformly in a downward straight line. When the airflow is blown out to the outside from the exhaust port 18, it flows uniformly in a straight line, and finally passes through the exhaust port 18 and a uniform airflow flowing in a straight line is discharged.

[0031] The feature of the present invention is that the flow path structure is designed to pass the airflow through four gas guide plates to generate a straightening effect, and the aperture of each cross section is combined with the curved gas space 162 to pass the airflow through each of the first gas guide plates 2 and the second gas guide plate 3 in the internal space 16, so that the airflow is respectively organized into airflows with different flow speeds and uniformity. When the airflow finally flows through the second gas guide hole 31, the uniformity of the airflow is improved and the straightened airflow flows uniformly in a straight line. As a result, the airflow discharged through the exhaust port 18 is uniformly distributed at an appropriate speed and flows in a straight line, which reliably prevents moisture and particles from being caught in the wafer case.

[0032] As shown in FIG. 7, the second embodiment of the air curtain device for a wafer case provided by the present invention is different from the first embodiment in that the casing 1a is formed by joining a left casing 11a and a right casing 12a together, and the three first gas guide plates 2a and the three second gas guide plates 3 are formed in an interchangeable structure, which changes the flow speed and uniformity of the airflow, and the airflow passes through the four gas guide plates to generate a straightening effect, which in turn increases the uniformity of the airflow, and the straightening flows uniformly in a straight line, which in turn reliably blocks particles and moisture. As a result, the airflow discharged through the exhaust port 18 has an appropriate speed, is uniformly distributed and flows in a straight line, which in turn reliably blocks moisture and particles, and prevents moisture and particles from being caught in the wafer case.

[0033] As shown in FIG. 8, the third embodiment of the air curtain device for a wafer case provided by the present invention is different from the first embodiment in that the casing 1b is integrally molded, and the three first gas guide plates 2b and the second gas guide plate 3 are formed in an interchangeable structure to change the flow speed and uniformity of the airflow. Similarly, the airflow passes through the four gas guide plates to generate a straightening effect, thereby performing the same function as the first embodiment, reliably blocking moisture and particles and preventing the moisture and particles from being caught in the wafer case. [Brief description of the drawings]

[0034] [Figure 1] FIG. 1 is a perspective view of a first embodiment of the present invention mounted on a wafer case load port. [Diagram 2] FIG. 2 is an exploded perspective view of the first embodiment of the present invention. [Diagram 3] FIG. 3 is a side view of the gas guide plate according to the first embodiment of the present invention in a state in which the casing internal space is extracted. [Figure 4] FIG. 4 is a cross-sectional view of a first embodiment of the present invention. [Diagram 5] FIG. 5 is a plan view of the first gas guide plate and the second gas guide plate of the first embodiment of the present invention. [Figure 6] FIG. 6 is a diagram showing a state in which the first embodiment of the present invention is used. [Figure 7] FIG. 7 is a side view of the internal space of a casing according to a second embodiment of the present invention. [Figure 8] FIG. 8 is a side view of the internal space of a casing according to a third embodiment of the present invention. [Explanation of symbols]

[0035] 1 Casing 1a Casing 1b Casing 11 Left plate member 12 Right plate member 13 Separation plate 14 Front plate member 15 Rear plate member 16 Interior Space 161 Sideways gas space 162 Curved Gas Space 163 Vertical gas space 17 Air Intake 18 Exhaust port 2. First gas guide plate 2a First gas guide plate 2b First gas guide plate 21 First gas guide hole 3 Second gas guide plate 31 Second gas guide hole 51 First Gas Space 52 Second Gas Space 53 The Third Gas Space 54 The Fourth Gas Space 6 Intake pipe 61 Exit 7 Wafer case load port 11a Left casing 12a Right casing D1 Cross-sectional diameter D2 Cross-sectional diameter D3 Cross-sectional diameter

Claims

1. An air curtain device for a wafer case, comprising a casing, at least one first gas guide plate, and a second gas guide plate, The casing has an internal space, and a cross section of the casing divides the internal space into a lateral gas space, a curved gas space communicating with the lateral gas space, and a vertical gas space communicating with the curved gas space, and the casing has at least one intake port communicating with the lateral gas space and an exhaust port communicating with the vertical gas space, At least one first gas guide plate is provided in the lateral gas space and / or the curved gas space, the first gas guide plate having a plurality of first gas guide holes; the second gas guide plate is provided at one end of the vertical gas space adjacent to the exhaust port, the second gas guide plate having a plurality of second gas guide holes; An air curtain device for a wafer case, characterized in that the number of the second gas guide holes is greater than the number of the first gas guide holes, and the total area of ​​each of the second gas guide holes on the second gas guide plate is greater than the total area of ​​each of the first gas guide holes on the first gas guide plate.

2. 2. The air curtain device for a wafer case according to claim 1, wherein the diameter of the cross section of the end of the vertical gas space is larger than the diameter of the cross section of the horizontal gas space and the diameter of the cross section of the curved gas space.

3. 3. The air curtain device for a wafer case as described in claim 2, wherein the cross-sectional diameter of the curved gas space is larger than the cross-sectional diameter of the horizontal gas space, and the cross-sectional diameter of the end of the vertical gas space is larger than the cross-sectional diameter of the curved gas space.

4. 2. The air curtain device for a wafer case as described in claim 1, wherein the number of the first gas guide plates is three, one of the first gas guide plates is installed in the lateral gas space, and the remaining two of the first gas guide plates are installed in the curved gas space.

5. 5. The air curtain device for a wafer case as described in claim 4, wherein the curved gas space is formed in a downward arc shape, and one of the remaining two first gas guide plates is installed at one horizontal end of the curved gas space, and the other is installed at one vertical end of the curved gas space.

6. 5. The air curtain device for a wafer case as described in claim 4, wherein each of the first gas guide plate and the second gas guide plate has a replaceable structure, and the flow speed and uniformity of the air flow passing through the first gas guide plate and the second gas guide plate are adjusted by changing the number and total area of ​​the first gas guide holes and the second gas guide holes.

7. 7. The air curtain device for a wafer case as claimed in claim 6, wherein the first gas guide holes are distributed uniformly or non-uniformly on the first gas guide plate to adjust the effect of air flow passing through.

8. 2. The air curtain device for a wafer case according to claim 1, wherein the casing is composed of a left plate member, a right plate member and a plurality of separation plates.

9. 2. The air curtain device for a wafer case as set forth in claim 1, wherein the casing is formed by joining a left casing and a right casing together.

10. 2. The air curtain device for a wafer case according to claim 1, wherein the casing is integrally formed.

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