Filter isolation for device front-end module

Abstract

Systems and methods for reducing boot time of a device front end module (EFEM) are disclosed herein. The EFEM may include an EFEM chamber formed between a plurality of walls, an upper plenum above the EFEM chamber, an upper plenum in fluid communication with the EFEM chamber, a plurality of conduits providing a return gas flow path to enable gas from the EFEM chamber to be recirculated to the upper plenum; one or more filters separating the upper plenum from the EFEM chamber; and an isolation gate configured to block the return gas flow path in response to the isolation gate being actuated to a closed position to isolate the one or more filters from the ambient environment in response to gas flow through the upper plenum when the EFEM chamber is open to the ambient environment.

Description

Technical Field

[0001] The present disclosure relates to electronic component manufacturing, and more particularly to equipment front end modules (EFEMs). Background Art

[0002] Substrate processing in semiconductor electronic component manufacturing is typically performed in multiple processing tools, where substrates are moved between processing tools in substrate carriers. The substrate carrier can dock with a load port (sometimes referred to as a factory interface (FI)) of an equipment front end module (EFEM), where one or more substrates are transferred to a load lock chamber, a transfer chamber, and / or a processing chamber. Front-to-back exposure of substrates to moisture and oxygen can lead to substrate corrosion (e.g., etching), interlayer defects (e.g., film stress and resistivity, physical vapor deposition), and component non-uniformity (e.g., chemical vapor deposition passivation). Eliminating moisture and oxygen from the EFEM environment can reduce and / or eliminate such component performance and yield challenges.

[0003] Some EFEMs provide a non-reactive environment for transferring substrates between a substrate carrier and a load lock and / or chamber. This is achieved by sealing the interior volume of the EFEM as much as possible and filling the interior volume with a gas that does not typically react with the substrate material (e.g., nitrogen). The non-reactive gas exhausts any reactive gases (e.g., oxygen) from the EFEM and also reduces / eliminates moisture in the EFEM. One or more loading ports for docking to one or more substrate carriers can be arranged along the front of the EFEM. The loading ports of conventional EFEMs are bottom purged with an inert gas to reduce the relative humidity (RH) and oxygen levels within the substrate carrier and EFEM during substrate processing and transportation.

[0004] When an EFEM is open to the surrounding environment, such as during maintenance of the EFEM, the interior of the EFEM is exposed to the surrounding environment. The relative humidity of the surrounding environment may typically be 30-40 times higher than the relative humidity when the EFEM is normally operating. The EFEM may include filters that absorb moisture from the surrounding environment when the EFEM is open to the surrounding environment. Once maintenance of the EFEM is completed and shut down for backup, a revalidation procedure is typically performed before the EFEM is returned to service. Because the moisture is absorbed by the filters of the EFEM and the interior of the EFEM is exposed to the surrounding environment, the revalidation process may take more than 24 hours, during which time the moisture absorbed by the filters is slowly removed. Such a lengthy revalidation process may be costly to the owner because the product cannot be processed until the revalidation process is complete. Summary of the invention

[0005] Disclosed herein, according to one or more specific embodiments, is an equipment front end module (EFEM), comprising an EFEM chamber formed between a plurality of walls of the EFEM and an upper air chamber located above the EFEM chamber. The upper air chamber is in fluid communication with the EFEM chamber. The EFEM further comprises a plurality of conduits providing a return gas flow path, the return gas flow path enabling gas to be recirculated from the EFEM chamber to the upper air chamber. The EFEM further comprises one or more filters, the filters separating the upper air chamber from the EFEM chamber. The EFEM further comprises an isolation gate, the isolation gate being configured to block the return gas flow path of the EFEM in response to the isolation gate being actuated to a closed position. When the isolation gate is in the closed position, the one or more filters are isolated from the surrounding environment in response to gas flowing through the upper air chamber when the EFEM chamber is open to the surrounding environment.

[0006] A method for maintaining an equipment front end module (EFEM) includes providing an EFEM with a plurality of conduits, the EFEM including an upper air chamber in fluid communication with an EFEM chamber through one or more filters and a plurality of conduits, the conduits providing a return gas flow path that enables gas from the EFEM to be recirculated to the upper air chamber. The method further includes opening the EFEM chamber to an external ambient environment and closing an isolation gate to block the return gas flow path. The method further includes causing gas to flow through a gas inlet of the upper air chamber and through one or more filters when the EFEM chamber is open to the external ambient environment, thereby preventing moisture from the ambient environment from being absorbed by the one or more filters. The method further includes closing the EFEM chamber to the external ambient environment and opening the isolation gate to clear the return gas flow path.

[0007] The isolation gate of the equipment front end module (EFEM) includes a body having a size that substantially corresponds to the size of the side wall of the upper air chamber of the EFEM. The isolation gate further includes one or more seals coupled to the side surface of the body. The one or more seals are configured to seal the corresponding openings at the periphery of the corresponding openings in the side wall of the upper air chamber. The isolation gate is configured to block the return gas flow path of the EFEM in response to the isolation gate being actuated to a closed position in the EFEM. BRIEF DESCRIPTION OF THE DRAWINGS

[0008] The drawings described below are for illustration purposes only and are not necessarily drawn to scale. The drawings are not intended to limit the scope of the present disclosure in any way.

[0009] Figure 1 A schematic top view of an electronic component manufacturing assembly according to one or more specific embodiments of the present disclosure is shown.

[0010] Figure 2A A schematic front view of an EFEM according to one or more specific embodiments of the present disclosure is shown.

[0011] Figure 2B A schematic side view of an EFEM according to one or more specific embodiments of the present disclosure is shown.

[0012] Figures 3A to 3B A schematic side view of an upper plenum system of an EFEM is shown, in accordance with one or more specific embodiments of the present disclosure.

[0013] Figures 4A to 4B A schematic cross-sectional partial view of an isolation gate and upper plenum of an EFEM is shown, in accordance with one or more specific embodiments of the present disclosure.

[0014] Figure 4C A schematic diagram of an isolation gate of an EFEM according to one or more specific embodiments of the present disclosure is shown.

[0015] Figure 5 A method of using an EFEM with an isolation gate according to one or more specific embodiments described herein is shown. DETAILED DESCRIPTION

[0016] Reference will now be made in detail to the exemplary embodiments of the present disclosure, examples of which are illustrated in the accompanying drawings. The same component symbols are used as much as possible in the drawings to refer to the same or similar parts. Unless otherwise specifically noted, the features of the various embodiments described herein may be combined with each other.

[0017] Described herein are specific embodiments of an EFEM that are configured to isolate one or more filters of the EFEM from the ambient environment during maintenance of the EFEM to reduce startup time after such maintenance. During maintenance of the EFEM, the EFEM may be opened and the interior of the EFEM may be exposed to a relatively high humidity ambient environment. Specifically, during maintenance and / or startup of the EFEM, one or more filters within the EFEM may be exposed to a relatively high relative humidity (RH) ambient gas (e.g., ambient air). Moisture is present in the ambient environment and adheres to all surfaces exposed to the ambient environment. Specifically, moisture in the ambient environment may be adsorbed into the filter media, such that when the EFEM begins operation (which may include circulating a low RH inert gas within the EFEM), the system may require a significant amount of time to reach a target RH level (e.g., 24 hours or more). Before the EFEM is ready to operate a product, the adsorbed moisture should be desorbed from all surfaces (including the filters). Therefore, the time required to return the EFEM to a low humidity level for product operation depends on the time its internal components are exposed to a relatively high humidity ambient environment, such as during startup or maintenance recovery. Isolating one or more filters in the EFEM from the surrounding environment creates an effective way to keep the filter media of the EFEM dry and not exposed to the higher ambient RH levels of the surrounding environment when the EFEM is open to the surrounding environment. This can be achieved by closing an isolation gate in the EFEM to block the return gas flow path between the EFEM chamber and the upper air chamber of the EFEM, and flowing a purge gas (e.g., a low humidity gas, such as a low RH xCDA) through an inlet in the upper air chamber toward the filter media. This creates a positive purge gas flow through the filter media while the interior of the EFEM is open to the surrounding environment, thereby preventing or reducing moisture in the surrounding air from contacting the filter media.

[0018] Known recirculating EFEMs do not have the ability to isolate the filter media to keep it dry when exposed to an ambient environment with a relatively high RH. For example, if the EFEM is being maintained, the filter will be exposed to ambient air within a semiconductor manufacturing facility. Typically, this ambient air has a RH of about 25% to about 50%, or about 30% to about 40%, or about 38%. During this maintenance period, the filter is exposed to the same high humidity level, while before maintenance (in the case of maintenance), the filter may have been operating at conditions below about 1% RH, which may be an operating goal. The EFEM door may be opened during maintenance to allow access to the internal components of the EFEM. Maintenance may be performed for a short amount of time (e.g., about 30 minutes), or may be performed for a longer amount of time (e.g., about 8 to about 10 hours). The longer the filter is exposed to ambient air with a higher RH level, the higher the moisture content adsorbed on the filter media, and therefore once sealed, the longer it will take to reduce the relative humidity level within the EFEM.

[0019] An EFEM according to one or more embodiments described herein includes an isolation gate that, together with an inert gas flow, isolates one or more filters of the EFEM from the surrounding environment and maintains the inert gas flow through the one or more filters of the EFEM while the EFEM is open to the surrounding environment. The isolation gate can be configured to block a return gas flow path between the EFEM chamber and an upper air chamber of the EFEM when the isolation gate is in a closed position. In response to the supply of inert gas to the upper air chamber, a positive pressure can be achieved (i.e., induced) in the upper air chamber. In some embodiments, the EFEM can be configured to flow gas through the filter in response to the positive pressure. Suitable inert, low RH gases include, but are not limited to, nitrogen (N 2 ), clean dry air (CDA), extremely clean dry air (xCDA) (i.e., CDA having a moisture content of less than about 0.33 ppm by weight), and the like. An inert gas can flow through the filter media, thereby isolating the filter media from ambient air. The isolation gate can be opened after the EFEM is shut down (e.g., after maintenance). This can greatly reduce the amount of moisture absorbed or adsorbed by one or more filters of the EFEM when the EFEM is open to the surrounding environment. As a result, such systems and equipment are able to start up and return to low RH operating levels suitable for substrate processing more quickly than conventional EFEMs. According to one or more specific embodiments of the present invention, the EFEM returns the RH of the inert gas to a baseline operating level as quickly as possible (e.g., on the order of minutes to hours), and much faster than a standard EFEM that does not include an isolation gate that can be closed during maintenance. The indoor ambient air has a relatively high RH compared to the target RH level during operation of the EFEM. When one or more filters within the EFEM remain exposed to ambient air, moisture can penetrate into the media and increase the time required to dry the media during startup. The filter media is essentially a large moisture absorber. Keeping the filter media dry can significantly reduce the startup time of the EFEM.

[0020] Figure 1 A schematic diagram of an example embodiment of an electronic component manufacturing assembly 100 according to one or more embodiments of the present disclosure is shown. The electronic component manufacturing assembly 100 may include a chassis 101 having a housing wall defining a transfer chamber 102. A transfer robot 103 (shown as a dashed circle) may be at least partially accommodated in the transfer chamber 102. The transfer robot 103 may be configured to place substrates to various destinations and remove substrates from various destinations by operation of an arm (not shown) of the transfer robot 103. The substrate described herein may refer to an article used to manufacture electronic components or circuit assemblies, such as a semiconductor wafer, a silicon-containing wafer, a patterned wafer, a glass plate, etc.

[0021] The movement of the various arm components of the transfer robot 103 can be controlled by appropriate commands to a drive assembly (not shown) including a plurality of drive motors of the transfer robot 103, such as commands from the controller 106. Signals from the controller 106 can cause movement of the various components of the transfer robot 103. Suitable feedback mechanisms can be provided for one or more components by various sensors such as position encoders.

[0022] As shown, transfer chamber 102 is square, but can also be rectangular, hexagonal, octagonal or other polygonal shapes, and can include first wall 102A, second wall 102B, third wall 102C and fourth wall 102D.In the specific embodiment shown, transfer robot 103 can transmit and / or retract dual substrate simultaneously.First wall 102A, second wall 102B, third wall 102C and fourth wall 102D can be planar, and the entrance into the group processing chamber can be arranged along corresponding wall.But other suitable shapes, wall and processing chamber quantity of mainframe housing 101 and the type of robot are also possible.

[0023] The destination of the transfer robot 103 may be any one or more of the processing chambers 108A-108F, which may be configured and operable to perform a process on the substrate transferred to the processing chambers 108A-108F. The process may be any suitable process, such as plasma vapor deposition (PVD) or chemical vapor deposition (CVD), etching, annealing, pre-cleaning, metal or metal oxide removal, etc. Other processes may be performed on the substrate therein.

[0024] The substrate may be received from the EFEM 114 into the transfer chamber 102 and may exit the transfer chamber 102 to the EFEM 114 via a load lock device 112 coupled to a rear wall 114R of the EFEM 114. The load lock device 112 may include one or more load lock chambers (e.g., load lock chambers 112A and 112B) therein. The load lock chambers 112A and 112B may be single wafer load lock (SWLL) chambers, multi-wafer chambers, or a combination thereof. Other numbers of load locks may be included.

[0025] The EFEM 114 may be a housing having various surrounding walls, such as a front wall 114F, a rear wall 114R, two side walls 114S1, 114S2, a top (not shown), and a bottom 114B, thereby forming an EFEM chamber 114C. Each of the front 114F, the rear 114R, and the two side walls 114S1, 114S2 may have one or more interface openings to facilitate substrate exchange and / or coupling to other components. Figure 1As shown, one or more load ports 115 may be disposed on a front wall (not shown) of the EFEM 114. The one or more load ports 115 may each be configured to receive and dock with a corresponding one or more substrate carriers 116 (e.g., FOUPs). Although four load ports 115 and four substrate carriers 116 are shown, other embodiments may have more or fewer load ports 115 adapted to dock a corresponding number of substrate carriers 116 at the EFEM 114.

[0026] The EFEM 114 may include a suitable loading / unloading robot 117 (shown in phantom) of conventional construction within its EFEM chamber 114C. Once the carrier door of the substrate carrier 116 is opened by the carrier door opener 119 for each load port 115, the loading / unloading robot 117 may be configured and operated to extract substrates from the substrate carrier 116 and feed the substrates through the EFEM chamber 114C and into one or more load lock chambers 112A and 112B of the load lock apparatus 112.

[0027] The side storage bays 120 may be coupled to the side walls 114S1 of the EFEM 114. Specifically, the loading / unloading robot 117 may be further configured to extract substrates from the side storage bays 120 and load substrates into the side storage bays 120 before and / or after processing in one or more of the processing chambers 108A-108F. In some specific embodiments, the loading / unloading robot 117 is a high-Z robot configured to access substrates stacked 26 layers high, or even 52 layers high or more in the side storage bays 120.

[0028] In the illustrated embodiment, the EFEM chamber 114C may be provided with an environmental control device to provide an environmentally controlled atmosphere therein. Specifically, the environmental control device 118 may be coupled to the EFEM 114 and may be operable to monitor and / or control environmental conditions within the EFEM chamber 114C. In some embodiments, and at certain times, the EFEM chamber 114C may receive a purge gas (e.g., an inert and / or non-reactive gas), such as argon (Ar), nitrogen (N2), etc., therein from a purge gas supply 118A. 2 ), helium (He), clean dry air, or extremely clean dry air (xCDA). The purge gas supply 118A may be coupled to the EFEM chamber 114C via appropriate conduits and one or more valves. The environmental conditions within the EFEM chamber 114C may be located inside a side storage container 124, which is located within and as part of the side storage compartment 120. The side storage container 124 receives substrates stacked vertically therein. In some specific embodiments, the side storage compartment 120 may have a substrate holder located therein to receive and support the substrates.

[0029] In more detail, the environmental control system 118 can control at least one of the following in the EFEM chamber 114C: (1) relative humidity (RH); (2) temperature (T); (3) oxygen (O 2 ) amount; and / or (4) the amount of purge gas. Other environmental conditions of the EFEM 114 may be monitored and / or controlled, such as the gas flow rate into the EFEM chamber 114C, or the pressure within the EFEM chamber 114C, or both.

[0030] In some embodiments, the environmental control system 118 includes a controller 106. The controller 106 may include appropriate processors, memory, and electronic components for receiving inputs from various sensors and for controlling one or more valves to control environmental conditions within the EFEM chamber 114C. In one or more embodiments, the environmental control system 118 may monitor relative humidity (RH) by sensing the RH in the EFEM 114 via sensor 130. Any suitable type of sensor that measures relative humidity may be used, such as a capacitive type sensor. The RH may be reduced by flowing an appropriate amount of purge gas from a purge gas supply 118A of the environmental control system 118 into the EFEM chamber 114C. In some embodiments, a low RH may be provided to the EFEM chamber 114C. 2 O level (e.g., purity greater than or equal to 99.9995%, H 2 Compressed bulk inert gas with a H 2 O content of 5 ppm or less (less than or equal to 5 ppm) may be used, for example, as the purge gas supply 118A in the environmental control system 118. Other suitably low H 2 O level.

[0031] In another aspect, the sensor 130 can measure a plurality of environmental conditions. For example, in some embodiments, the sensor 130 can measure a relative humidity value as described above. In one or more embodiments, the predefined reference relative humidity value can be less than 1000 ppm humidity, less than 500 ppm humidity, or even less than 100 ppm humidity, depending on the humidity level that can be tolerated by a particular process in the electronic component manufacturing assembly 100 or a particular substrate exposed to the EFEM 114 environment.

[0032] An environmental monitor (eg, sensor 130) may also measure oxygen (O 2 In some embodiments, a control signal from the controller 106 to the environmental control device 118 may cause an appropriate amount of purge gas to begin flowing from the purge gas supply 118A into the EFEM chamber 114C to control the oxygen (O 2 ) is lower than O 2 In one or more specific embodiments, O 2The threshold may be less than 50 ppm, less than 10 ppm, or even less than 5 ppm, depending on the amount of O that is tolerable (without affecting quality) for the particular process being performed. 2 level, such processing is performed in electronic component manufacturing assembly 100 or a particular substrate exposed to the environment of EFEM 114. In some embodiments, sensor 130 may sense the oxygen level in EFEM chamber 114C to ensure that it is above a safe threshold level allowed into EFEM chamber 114C.

[0033] The sensor 130 may further measure an absolute or relative pressure within the EFEM 114. In some embodiments, the controller 106 may control the flow of purge gas from the purge gas supply 118A into the EFEM chamber 114C to control the pressure within the EFEM chamber 114C.

[0034] In the embodiment shown herein, the controller 106 may include a processor, memory, and peripheral components configured to receive control inputs (e.g., relative humidity and / or oxygen) from the sensor 130 and execute a closed loop control or other appropriate control scheme. In one embodiment, the control scheme may vary the flow rate of the purge gas introduced into the EFEM 114 to achieve a predetermined environmental condition therein. In another embodiment, the control scheme may determine when to transfer a substrate into the EFEM 114 or when to open a door of the substrate carrier 116. In some embodiments, the controller 106 may control the opening and / or closing of gates included in the EFEM chamber 114C that direct the flow of the purge gas through one or more filters included in the EFEM chamber 114C.

[0035] The side storage compartment 120 attached to the EFEM 114 can store substrates under specific environmental conditions. For example, the side storage compartment 120 can store substrates under the same environmental conditions as those present in the EFEM chamber 114C, except that the gas flow rate in the side storage compartment 120 can be different (e.g., significantly greater). The side storage compartment 120 can be fluidly coupled to the EFEM chamber 114C and can receive gas (e.g., purge gas) from the EFEM chamber 114C. The side storage compartment 120 can include an exhaust conduit 132 to exhaust gas from the side storage compartment 120, which further enables the substrates stored in the side storage compartment 120 to be continuously exposed to the desired environmental conditions and purge gas flow rate.

[0036] In some specific embodiments, the side storage compartment 120 can receive one or more vertically aligned side storage containers 124. For example, a first side storage container 124 can be accommodated in the side storage compartment 120. The first side storage container 124 can include an opening 126 facing the EFEM chamber 114C. The first side storage container 124 can also include an exhaust chamber 128 located opposite the opening 126. The exhaust chamber 128 can be coupled to an exhaust duct 132, which can be coupled between the exhaust chamber 128 and the exterior of the side storage compartment 120.

[0037] The first exhaust conduit 132 may be composed of an inner portion and a first outer portion 132A. The second conduit may be coupled between the second side storage containers and may include a second outer portion 134B. Both the first outer portion 134A and the second outer portion 134B may be located within the cover 136. In some embodiments, the cover 136 (rather than the first outer portion 134A and the second outer portion 134B) may be used as a conduit to discharge exhaust gas from the side storage containers 124 and 224. In other embodiments, the first outer portion 134A and the second outer portion 134B may pass through the interior of the side storage compartment 120.

[0038] Figure 2A A schematic top view of an electronic component manufacturing assembly according to one or more specific embodiments of the present disclosure is shown. Figure 2B A schematic side view of an electronic component manufacturing assembly according to one or more specific embodiments of the present disclosure is shown.

[0039] Specific embodiments of EFEM systems suitable for including isolation gates according to specific embodiments herein are described in Figure 2A and 2B 1. As with EFEM 114, substrates may be received from EFEM 200 into a transfer chamber (not shown) and may exit the transfer chamber to EFEM 200 through a load lock device (not shown) coupled to a wall of EFEM 200. The load lock device may include one or more load lock chambers. The load lock chamber may be a single wafer load lock (SWLL) chamber, a multi-wafer chamber, or a combination thereof.

[0040] The EFEM 200 may be an enclosure having various enclosure walls, such as a front wall, a rear wall, two side walls, a top, and a bottom, thereby forming an EFEM chamber 214. Each of the front wall, the rear wall, and the two side walls may have one or more interface openings to facilitate substrate exchange and / or coupling to other components. One or more loading ports 215 may be disposed on a wall of the EFEM 200, such as Figure 2AAs shown. The one or more load ports 215 can each be configured to receive and dock with a corresponding one or more substrate carriers (e.g., FOUPs). Although four load ports 215 are shown, other embodiments can have more or fewer load ports 215 suitable for docking a corresponding number of substrate carriers at the EFEM 200.

[0041] In the illustrated embodiment, the EFEM chamber 214 may be provided with an environmental control device to provide an environmentally controlled atmosphere therein. Specifically, the environmental control device (not shown) may be coupled to the EFEM 200 and may be operable to monitor and / or control environmental conditions within the EFEM chamber 214. In some embodiments, the EFEM chamber 214 may receive a purge gas (e.g., an inert and / or non-reactive gas) such as argon (Ar), nitrogen (N2), or the like from a purge gas supply therein. 2 ), helium (He), clean dry air, or extremely clean dry air (xCDA). The environmental control system can control at least one of the following within the EFEM chamber 214: (1) relative humidity (RH); (2) temperature (T); (3) oxygen (O 2 ) amount; and / or (4) the amount of purge gas. Other environmental conditions of the EFEM 200 may be monitored and / or controlled, such as the gas flow rate into the EFEM chamber 214, or the pressure within the EFEM chamber 214, or both.

[0042] In some embodiments, the environmental control system includes a controller (not shown). The controller may include appropriate processors, memory, and electronic components for receiving inputs from various sensors and for controlling one or more valves to control environmental conditions within the EFEM chamber 214. In one or more embodiments, the environmental control system may monitor relative humidity (RH) by sensing the RH in the EFEM 214 via a sensor. Any suitable type of sensor that measures relative humidity may be used, such as a capacitive type sensor. The RH may be reduced by flowing an appropriate amount of purge gas from a purge gas supply of the environmental control system into the EFEM chamber 214. In some embodiments, a system having a low RH may be used to control the RH in the EFEM chamber 214. 2 O level (e.g., purity greater than or equal to 99.9995%, H 2 Compressed bulk inert gas with a H2O content of 5 ppm or less can be used as the purge gas supply in the environmental control system. Other appropriately low H2O 2 O level.

[0043] In another aspect, the sensor can measure multiple environmental conditions. For example, in some embodiments, the sensor can measure a relative humidity value as described above. In one or more embodiments, the predefined reference relative humidity value can be less than 1000 ppm humidity, less than 500 ppm humidity, or even less than 100 ppm humidity, depending on the humidity level that can be tolerated by a particular process in the electronic component manufacturing assembly 100 or a particular substrate exposed to the EFEM 214 environment.

[0044] The environmental control system can also measure the oxygen (O 2 In some embodiments, a control signal from the controller to the environmental control device may cause an appropriate amount of purge gas to begin flowing from the purge gas supply into the EFEM chamber 214 to control the oxygen (O 2 ) is lower than O 2 In one or more specific embodiments, O 2 The threshold may be less than 50 ppm, less than 10 ppm, or even less than 5 ppm, depending on the amount of O that is tolerable (without affecting quality) for the particular process being performed. 2 level, this process is performed in the electronic component manufacturing assembly 100 or a specific substrate exposed to the environment of the EFEM 200. In some embodiments, a sensor can sense the oxygen level in the EFEM chamber 214 to ensure that it is above a safe threshold level allowed into the EFEM chamber 214.

[0045] The sensor may further measure the absolute or relative pressure within the EFEM 200. In some embodiments, the controller may control the flow of purge gas from the purge gas supply into the EFEM chamber 214 to control the pressure in the EFEM chamber 214.

[0046] The controller may include a processor, memory, and peripheral components configured to receive control inputs (e.g., relative humidity and / or oxygen) from sensors and execute closed loop control or other appropriate control schemes. In one embodiment, the control scheme may vary the flow rate of the purge gas introduced into the EFEM 200 to achieve predetermined environmental conditions therein. In another embodiment, the control scheme may determine when to transfer a substrate into the EFEM 200 or when to open a door of a substrate carrier.

[0047] The chemical filter and the particle filter 207, 209 within the EFEM 200 may be isolated by an isolation gate anywhere within the recirculation ducts 228, 229, respectively. Figure 2AAs shown, the gas may be ducted to the filter media using one or more fan systems 210. In some embodiments, the filter may be isolated in a return path (e.g., duct 229) to keep the filter media dry. The gas inlet 212 (e.g., of the plenum 230) may be configured to receive a low RH inert purge gas to replace ambient air with a high RH gas during maintenance events or installations. In some embodiments, during normal operation of the EFEM 200, the purge gas may be recirculated during maintenance to reduce consumables. As shown in FIG. Figure 2B As shown, the gas may flow upward through ducts 228, 229. The gas may enter a plenum 230 above the chemical and particulate filters 207, 209. The fan unit 210 may pull the recirculated gas and force the gas through the filters 207, 209 so that it flows downward 232 to the EFEM chamber 214.

[0048] The EFEM chamber and / or the upper plenum of the EFEM may include doors or panels that may be opened or removed to provide access to the interior of the EFEM chamber and / or the upper plenum. The EFEM may undergo periodic maintenance during which the EFEM chamber and / or the upper plenum may be exposed to the surrounding environment.

[0049] Figures 3A to 3B A schematic side view of an upper plenum system of an EFEM is shown, in accordance with one or more specific embodiments of the present disclosure. Figure 3A The upper plenum system 300 is shown with the isolation gate 308 in an open position, and Figure 3B The upper plenum system 300 is shown with the isolation gate 308 in a closed position.

[0050] In some specific embodiments, Figure 3A As shown, gas may be introduced from an EFEM chamber (e.g., an EFEM substrate transfer chamber) substantially below the upper plenum 330 through conduit 329 (e.g., Figure 2A228, 229) flows back to the upper air chamber 330. When the isolation gate 308 is in the open position, gas can move into the upper air chamber 330 through one or more openings (for example, by one or more fans 310 disposed near each opening). The isolation gate 308 can be opened during normal operation of the EFEM. In some specific embodiments, the actuator 340 can move the isolation gate 308 between the open position and the closed position. In some specific embodiments, the actuator 340 is a pneumatic actuator. Alternatively, the actuator can be an electronic actuator, a magnetic actuator, or other type of actuator. In the case of a pneumatic actuator, the actuator 340 can be actuated in response to receiving a supply of gas or fluid. In some examples, the actuator 340 receives the same type of gas as the purge gas described below (for example, an inert gas, CDA, etc.). In some specific embodiments, the actuator 340 is a linear actuator. When isolation gate 308 is in the open position, gas moved into upper plenum 330 (e.g., by fan 310) can pass through chemical filter 307 and / or particulate filter 309 and enter EFEM chamber 332. Gas can be recirculated through duct 329 and fan 310 as long as isolation gate 308 is in the open position.

[0051] like Figure 3B As shown, in some embodiments, in response to the EFEM chamber 332 being opened to the surrounding environment (e.g., for maintenance), the isolation gate 308 can be closed. In some embodiments, the actuator 340 actuates the isolation gate 308 to the closed position. When in the closed position, the isolation gate 308 can prevent air flow through the fan 310. In some embodiments, the isolation gate 308 seals the fan opening so that no gas can enter or leave the upper plenum 330 through the fan 310. In some embodiments, the isolation gate 308 can prevent gas from flowing through the duct 329. In some examples, the isolation gate 308 is substantially disposed within the duct 329.

[0052] In some embodiments, a controller (not shown) can control actuation of the isolation gate 308. The controller can receive sensor data from one or more sensors, and in response to this data, the controller can cause the actuator 340 to open or close the isolation gate. In some examples, the controller receives sensor data from a door sensor that detects when a maintenance door of the EFEM chamber is opened. The controller can cause the isolation gate 308 to close in response to the door sensor detecting that the maintenance door is open. In some embodiments, the controller receives sensor data from a humidity sensor, an oxygen sensor, or a humidity sensor. 2) sensor and / or one or more other environmental sensors that detect conditions within the EFEM chamber. The controller may initiate an isolation protocol action in response to the sensor data indicating a triggering condition. The initiating action may include closing the isolation gate 308. For example, the controller may cause the isolation gate 308 to close in response to receiving sensor data indicating that the relative humidity within the EFEM chamber exceeds a threshold humidity condition. In another example, the controller may cause the isolation gate 308 to close in response to receiving sensor data indicating that the oxygen level within the EFEM chamber exceeds a threshold oxygen condition. The controller may cause the purge gas to be supplied through the opening 312 in response to the closing of the isolation gate 308, as explained below. In some specific embodiments, the isolation gate 308 may be manually actuated (e.g., by a technician, etc.).

[0053] A purge gas flow can be supplied to the upper plenum 330 through opening 312. Isolation gate 308 can prevent purge gas from flowing through conduit 329. In some specific embodiments, the purge gas is a low RH gas as described above. For example, the purge gas can be CDA. The purge gas can be supplied to the upper plenum 330 at an elevated pressure. In some examples, the purge gas is supplied through opening 312 at a pressure greater than 10 pounds per square inch (PSI). In some examples, the purge gas is supplied at a pressure greater than 20 PSI, greater than 30 PSI, or greater than 50 PSI. The supply of purge gas can create a positive pressure within the upper plenum 330. The closed isolation gate 308 can seal conduit 329 to the purge gas (e.g., at a positive pressure in the upper plenum 330), allowing the purge gas to pass through the chemical filter 307 and / or the particle filter 309 and enter the EFEM chamber 332. By passing the purge gas through the chemical filter 307 and / or the particle filter 309, when the EFEM chamber 332 is open to the surrounding environment, moisture in the ambient air can be prevented from accumulating in or on the chemical filter 307 and / or the particle filter 309. In some specific embodiments, the supply of the purge gas can be controlled (e.g., increased and / or decreased) to adjust the noise in the EFEM chamber 332. In some examples, reducing the flow rate and / or pressure of the purge gas supply can reduce the noise within the EFEM chamber 332 to below a threshold noise level.

[0054] Figures 4A to 4B A schematic cross-sectional partial view of an isolation gate and upper plenum of an EFEM is shown, in accordance with one or more specific embodiments of the present disclosure. Figure 4CSchematic diagram of an isolation gate of an EFEM according to one or more embodiments of the present disclosure is shown. In some embodiments, isolation gate 408 includes plate 408A, one or more gaskets (e.g., seal 408B) attached to plate 408A, and support 408C attached to plate 408A. In some embodiments, support 408C is connected to an actuator (e.g., Figure 3A and Figure 3B The support 408C can support the isolation gate 408 laterally and / or vertically in space. In some embodiments, the support 408C is in the open position (e.g., Figure 4A shown) and the closed position (e.g. Figure 4C ) to push and / or pull the isolation gate 408 between the open position and the closed position. In some specific embodiments, the isolation gate 408 includes a plurality of supports. In some examples, the isolation gate 408 includes a first support (e.g., one or more guide rails) for supporting the isolation gate 408 in a vertical direction and / or a second support for supporting the isolation gate 408 in a lateral direction. In some examples, the isolation gate 408 is configured to be supported by one or more supports and is configured to be connected to a linkage for actuating the isolation gate 408 between an open position and a closed position.

[0055] like Figure 4A 4, the isolation gate 408 can be shown in an open position. In some embodiments, when the isolation gate 408 is in an open position, gas can be recirculated (e.g., from the EFEM chamber) to the upper plenum 430 through one or more conduits 429. In some embodiments, the gas flows through the fan 410. In some examples, the gas can flow through the fan opening 410C (e.g., an opening in the side wall of the upper plenum 430), past the fan blades 410B, and can be directed into the upper plenum through the fan shroud 410A.

[0056] like Figure 4BAs shown, the isolation gate 408 can be shown as being in a closed position. In some embodiments, the isolation gate 408 can be closed when the EFEM chamber is open to the surrounding environment (e.g., the door of the EFEM chamber is open to the external environment). In some embodiments, one or more actuators (e.g., pneumatic actuators) can close the isolation gate 408 in response to the EFEM chamber being opened. A gas supply (e.g., purge gas, CDA, low humidity air, etc.) can be provided to the upper air chamber (e.g., through the gas inlet 212 of Figure 2 or the opening 312 of Figure 3). The isolation gate 408 can be closed (e.g., actuated to a closed position) so that gas cannot flow through the fan opening 410C and flow through the duct 429 (e.g., preventing gas from flowing from the upper air chamber to the EFEM chamber through the fan opening 410C). In some embodiments, closing the isolation gate 408 causes the gas supply to flow from the upper air chamber through one or more filters (e.g., Figure 3A and 3B Filters 307, 309, Figure 2A and 2B The gas flowing through the one or more filters when the isolation gate 408 is closed, and the gas supplied to the upper plenum 430, can functionally isolate the one or more filters from the surrounding environment when the EFEM chamber is open.

[0057] In some embodiments, in response to the isolation gate 408 being actuated to the closed position, the seal 408B can engage the surface of the peripheral edge near the fan opening 410C. In some embodiments, the seal 408B can be deformed in response to the applied force (e.g., through the plate 408A and / or the support 408C by the actuator). In some embodiments, the seal 408B may have a D-shaped cross-section. In other embodiments, the seal 408B may have a substantially square cross-section. In other embodiments, the seal 408B may have a circular cross-section or a semicircular cross-section. Other cross-sectional shapes are also possible. The seal 408B may be hollow. In some embodiments, the seal 408B is made of a polymer. For example, the seal 408B may be made of a closed-cell foam rubber material (e.g., made of a closed-cell foam rubber material). In some embodiments, the seal 408B is made of a chemically resistant material (e.g., a corrosion-resistant material, etc.).

[0058] In some embodiments, seal 408B is attached to plate 408A. In some examples, seal 408B can be attached to plate 408A by an adhesive and / or by one or more fasteners and / or clamping mechanisms. In some embodiments, isolation gate 408 includes a plurality of seals 408B, each seal corresponding to a fan opening of the EFEM. In some examples, such as Figure 4CAs shown, the isolation gate 408 may include three seals 408B. However, in other examples, the isolation gate 408 may include five seals 408B or any other number of seals, each of which corresponds to the fan opening 410C. In some specific embodiments, in order to prevent bending, the plate 408A may include one or more reinforcement features. In some examples, the plate 408A may include a reinforcement attached to the back of the plate 408A. In some examples, the plate 408A may include structural features to increase the area moment of inertia of the cross section of the plate 408A. In some specific embodiments, the reinforcement and / or structural features included in the plate 408A can help the plate 408A resist bending under load (e.g., under the load of the force applied by the actuator to seal the fan opening 410C). In some specific embodiments, the plate 408A may be made of (e.g., composed of) materials such as stainless steel, carbon steel, aluminum and / or chrome. In some specific embodiments, the plate 408A may include a protective coating on at least a portion of the surface of the plate 408A. In some examples, plate 408A includes an anodized coating. The protective coating may be a corrosion resistant coating. Plate 408A may be configured to be connected to one or more actuators (e.g., Figure 3A and Figure 3B actuator 340).

[0059] Figure 5 A method 500 for maintaining an EFEM using an isolation gate according to one or more embodiments described herein is shown. At block 502, the method includes providing an EFEM. The EFEM may include an upper plenum in fluid communication with the EFEM chamber through one or more filters. The EFEM may further include a plurality of conduits providing a return gas flow path that enables gas to be recirculated from the EFEM chamber to the upper plenum. In one or more embodiments, the EFEM is taken offline to perform a maintenance event or is taken offline for initial installation and / or startup.

[0060] At block 504, a specific embodiment of method 500 includes opening the EFEM chamber to an external ambient environment. For example, a door of the EFEM chamber may be opened to expose the internal components to the ambient environment. The relative humidity of the air in the ambient environment is generally higher than the target RH for operation within the EFEM.

[0061] At block 506, method 500 includes closing the isolation gate to block the return gas flow path formed by the plurality of conduits. In some embodiments, the isolation gate may be closed by one or more actuators coupled to the isolation gate. According to one or more embodiments, when in the closed position, the isolation gate may seal one or more openings (e.g., fan openings) of the upper plenum to prevent gas from flowing through the openings.

[0062] At block 508, method 500 includes flowing a low RH purge gas through a gas inlet of the upper air chamber and through one or more filters while the EFEM chamber is open to the external ambient environment. The low RH purge gas may be pressurized to provide a positive flow rate of the purge gas through the one or more filters. A positive pressure may be generated within the upper air chamber by supplying the purge gas. When the EFEM is operating, an isolation gate may prevent the gas supply from flowing through a conduit for gas recirculation (e.g., a return gas flow path). When contacting internal components of the EFEM chamber, the purge gas flows through a filter medium, preventing moisture in the ambient environment from being absorbed by the one or more filters. The purge gas flow continues until the maintenance work is completed. The low RH inert gas may be the same low RH intermediate gas used during EFEM operation, or it may be a different gas at a different RH below the RH of the ambient environment.

[0063] At block 510, method 500 includes closing the EFEM chamber. Once the EFEM chamber is closed, the EFEM is activated to return to its target operating condition. After isolating the one or more filters from the high RH ambient environment, the EFEM may become operational again in less than about 7 hours, less than about 6 hours, less than about 5 hours, less than about 4 hours, less than about 3 hours, or any single value or sub-range within these ranges.

[0064] At block 512, method 500 includes opening an isolation gate to clear a return gas flow path. The isolation gate may be opened by one or more actuators. When the isolation gate is opened, gas may be recirculated from the EFEM chamber to the upper plenum through the conduit.

[0065] A comparison of system service events at a baseline is performed relative to a device isolated using a filter according to one or more embodiments herein. In one example, the EFEM system is turned on and exposed to ambient humidity for a predetermined time interval, and the time to return to an operational control mode level is measured. In a second example, the filter is isolated according to at least one embodiment herein and the system is exposed to ambient humidity for the same predetermined time interval. The time to return to an operational control mode level is measured.

[0066] The systems and methods described herein significantly reduce the startup time of the EFEM compared to conventional EFEMs. For example, if the door of a conventional EFEM chamber is opened to expose the internal components and filter media to outside air at a RH of about 30% to about 40% for about 30 minutes, the time it will take to restart the EFEM and reduce the RH of the gas to a target of less than about 1% will be about 8 hours to about 12 hours, or about 8.5 hours to about 10 hours, or any individual value or sub-range within these ranges. In contrast, according to one or more specific embodiments of the EFEM and related methods of use described herein, in which the filter is isolated and purged with low RH gas during a 30-minute maintenance period, the time required to restart the EFEM and reduce the RH of the gas to a target of less than about 1% will be about 3 hours to about 7 hours, or about 4 hours to about 6 hours, or 6 hours, or any individual value or sub-range within these ranges. In some embodiments, the EFEM and related methods according to embodiments herein reduce the time taken to restart the EFEM after maintenance by about 12.5% ​​to about 75%, about 15% to about 62.5%, about 25% to about 50%, or any individual value or sub-range within these ranges. In some embodiments, if the maintenance is two hours, the restart of the EFEM of the present invention is about 40% faster than a conventional EFEM. For example, reducing the startup time by about half can bring a production system back online faster, thereby increasing revenue and reducing costs.

[0067] References in this specification to "in one specific embodiment", "in some specific embodiments", "in one or more specific embodiments", or "in a specific embodiment", etc., indicate that the specific features, structures, or characteristics associated with the specific embodiment described are included in at least one specific embodiment of the present disclosure. Therefore, the phrases "in one or more specific embodiments", "in some specific embodiments", "in one specific embodiment", or "in a specific embodiment", etc., which appear in various places throughout this specification, do not necessarily refer to the same specific embodiment of the present disclosure. In addition, specific features, structures, configurations, or characteristics may be combined in any suitable manner in one or more specific embodiments.

[0068] As used herein, the singular forms "a," "an," and "the" include plural references unless the context clearly dictates otherwise. Thus, for example, reference to "a robotic arm" includes a single robotic arm as well as more than one robotic arm.

[0069] The word "about" as used herein in connection with measured values ​​refers to the normal variation in the measured values ​​that can be expected by one of ordinary skill in the art when the measurements are made with a degree of care commensurate with the purpose of the measurement and the accuracy of the measuring equipment. In certain specific embodiments, the word "about" includes ±10% of the referenced number, such that "about 10" will include 9 to 11.

[0070] The term "at least about" in relation to a measured value refers to the normal variation in the measured value that can be expected by a person of ordinary skill in the art when measuring with a degree of care commensurate with the purpose of the measurement and the accuracy of the measuring equipment, as well as any value above this value. In certain specific embodiments, the term "at least about" includes the number listed minus 10% and any value higher, so that "at least about 10" will include 9 and any value greater than 9. This term may also be expressed as "about 10 or more". Similarly, the term "less than about" generally includes the number listed plus 10% and any lower number, so that "less than about 10" includes 11 and any number less than 11. This term may also be expressed as "about 10 or less".

[0071] Unless otherwise indicated, all parts and percentages are by weight. Unless otherwise indicated, weight percentages (wt%) are based on the entire composition excluding any volatile matter (ie, based on dry solids content).

[0072] The foregoing description discloses example specific embodiments of the present case. Modifications of the above-mentioned components, devices and methods that fall within the scope of the present disclosure will be apparent to those of ordinary skill in the art. Therefore, although the present disclosure has been disclosed in conjunction with example specific embodiments, it should be understood that other specific embodiments may also fall within the scope of the present disclosure as defined by the claims.

Claims

1. An equipment front end module (EFEM), comprising: an EFEM chamber formed between a plurality of walls of the EFEM; an upper air chamber, the upper air chamber being above the EFEM chamber, the upper air chamber being in fluid communication with the EFEM chamber; a plurality of conduits providing a return gas flow path that enables gas to be recirculated from the EFEM chamber to the upper plenum; one or more filters, the one or more filters separating the upper plenum from the EFEM chamber; as well as an isolation gate configured to block the return gas flow path in response to the isolation gate being actuated to a closed position, wherein when the isolation gate is in the closed position, the one or more filters are isolated from the ambient environment in response to gas flowing through the upper plenum when the EFEM chamber is open to the ambient environment.

2. The EFEM according to claim 1, further comprising: One or more actuators configured to actuate the isolation gate between an open position and the closed position.

3. The EFEM of claim 2, wherein the one or more actuators are pneumatic actuators. 4 . The EFEM of claim 1 , wherein the gas is a purge gas, and wherein the upper plenum comprises a gas inlet configured to receive the purge gas.

5. The EFEM of claim 4, wherein the EFEM is configured to flow the purge gas from the upper plenum through the one or more filters to the EFEM chamber to achieve a positive pressure in the upper plenum.

6. The EFEM of claim 1, wherein the isolation gate comprises one or more gaskets to seal the plurality of conduits.

7. The EFEM of claim 6, wherein the one or more washers are comprised of a closed-cell foam rubber material.

8. The EFEM of claim 1, further comprising one or more openings along the return gas flow path between the plurality of tubes and the upper plenum, wherein the isolation gate is configured to seal the one or more openings at peripheral edges of the one or more openings.

9. The EFEM of claim 8, further comprising one or more fans disposed proximate each of the one or more openings, wherein the one or more fans are configured to recirculate gas from the EFEM chamber to the upper plenum through the plurality of ducts and the one or more openings.

10. The EFEM of claim 1, wherein the isolation gate is composed of stainless steel, aluminum, carbon steel, chrome, or a combination thereof.

11. The EFEM of claim 10, wherein the isolation gate comprises a protective coating.

12. A method for maintaining an equipment front end module (EFEM), the method comprising the steps of: The EFEM is provided, and the EFEM comprises: an upper plenum in fluid communication with the EFEM chamber through one or more filters; and a plurality of conduits providing a return gas flow path that enables gas to be recirculated from the EFEM chamber to the upper plenum; opening the EFEM chamber to the external surrounding environment; closing the isolation gate to block the return gas flow path; allowing gas to flow through the gas inlet of the upper gas chamber and through the one or more filters when the EFEM chamber is open to the external ambient environment, thereby preventing moisture from the ambient environment from being absorbed by the one or more filters; sealing the EFEM chamber from the external ambient environment; and The isolation gate is opened to clear the return gas flow path.

13. The method according to claim 12, further comprising the steps of: A positive pressure is generated inside the upper plenum in response to the gas flowing through the gas inlet.

14. The method of claim 12, wherein the gas is blocked by the isolation gate from flowing from the upper plenum through the plurality of conduits to the EFEM chamber when the isolation gate is in a closed position.

15. The method of claim 12, wherein the external ambient environment comprises gas at a first relative humidity, the first relative humidity being approximately 30 to 40 times higher than a second relative humidity of the EFEM chamber during operation of the EFEM.

16. The method of claim 12, wherein the gas comprises a purge gas.

17. The method of claim 16, wherein the purge gas comprises clean dry air (CDA).

18. An isolation gate of an equipment front end module (EFEM), the isolation gate comprising: a body having dimensions substantially corresponding to the dimensions of the side walls of the upper plenum of the EFEM; and one or more seals coupled to a side of the body, wherein the one or more seals are configured to seal the corresponding openings in the side wall of the upper plenum at a periphery of the corresponding openings, Wherein the isolation gate is configured to block a return gas flow path of the EFEM in response to the isolation gate being actuated to a closed position in the EFEM.

19. The isolation gate of claim 18, wherein the isolation gate is further configured to be coupled to one or more actuators to actuate the isolation gate between an open position and the closed position.

20. The isolation gate of claim 18, wherein the isolation gate is composed of stainless steel, aluminum, carbon steel, chrome, or a combination thereof.

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