System for transferring wafer substrates, method for reducing relative humidity, and method for reducing air flow

Abstract

Embodiments of the present disclosure relate to systems and methods for reducing humidity within a front opening unified pod when the front opening unified pod is loaded onto an equipment front end module during a manufacturing process and for transferring semiconductor wafer substrates. A deflector of specified structure is placed within the equipment front end module above the load port of the front opening unified pod. The deflector directs airflow within the equipment front end module away from the load port. The deflector includes a body having a plurality of holes in the body of the deflector and having a sloped front surface. As a result, the penetration of high humidity air from the equipment front end module into the front opening unified pod is reduced.

Description

Technical Field

[0001] The present invention relates to a system for transferring wafer substrates, a method for reducing relative humidity, and a method for reducing airflow. Background Technology

[0002] Semiconductor integrated circuits can be manufactured using a variety of processes, such as thermal oxidation, diffusion, ion implantation, RTP (rapid thermal processing), CVD (chemical vapor deposition), PVD (physical vapor deposition), etching, and photolithography. Semiconductor wafer substrates are placed in a front-opening unified pod (FOUP) for storage between process steps and transport between various process machines. Summary of the Invention

[0003] According to one embodiment of the present invention, a processing system transfers a semiconductor wafer substrate to a processing module including a device front-end module (EFEM), at least one deflector, and a process module. The EFEM has at least one loading port on its side and a fan filter unit on its top, the fan filter unit generating a downward laminar airflow within the device front-end module. The deflector, located on the inner surface of the device front-end module above the at least one loading port and below the fan filter unit, is used to guide the laminar airflow away from the at least one loading port and includes a body having a sloped or curved front surface, a rear surface adjacent to the inner surface of the device front-end module, and a plurality of parallel channels extending from the upper surface of the body to a lower surface of the body angled to the upper surface. The process module is configured to receive the semiconductor wafer substrate from the device front-end module when a front-opening transfer cassette containing the semiconductor wafer substrate is loaded at the at least one loading port.

[0004] According to an embodiment of the present invention, a method for reducing the relative humidity in a front-aperture transfer box is used during semiconductor wafer substrate transfer and includes the following steps: Loading the front-aperture transfer box at the loading port of a device front-end module. Opening the door of the front-aperture transfer box. Deflecting downward gas generated by a fan filter unit away from the loading port using a deflector located on the inner surface of the device front-end module above the loading port, wherein the deflector includes a body having an inclined or curved front surface, a rear surface adjacent to the inner surface of the device front-end module, and a plurality of parallel channels extending from an upper surface of the body to a lower surface of the body at an angle to the upper surface. Blowing the front-aperture transfer box with a purge gas flow.

[0005] According to an embodiment of the present invention, a method for reducing airflow from a device front-end module into a front-opening transfer box is used during semiconductor wafer substrate transfer and includes the following steps: A deflector is mounted on an inner surface above the loading port of the device front-end module, wherein the deflector guides laminar airflow away from the loading port. The deflector includes a body having an inclined or curved front surface, a rear surface adjacent to the inner surface of the device front-end module, and a plurality of parallel channels extending from an upper surface of the body to a lower surface of the body at an angle to the upper surface. Attached Figure Description

[0006] The nature of this disclosure will be best understood when read in conjunction with the accompanying drawings in a detailed description. It should be noted that, in accordance with industry standard practice, the various features are not drawn to scale. In fact, the dimensions of the various features may be arbitrarily increased or decreased for clarity of explanation.

[0007] Figure 1 It is the Front Opening Unified Pod (FOUP) used in some embodiments of this disclosure.

[0008] Figure 2 This is a front perspective view of an Equipment Front End Module (EFEM) according to some embodiments of the present disclosure.

[0009] Figure 3 This is a side sectional view of an EFEM according to some embodiments of the present disclosure.

[0010] Figure 4 This is a rear perspective view of a first embodiment of a deflector according to some embodiments of the present disclosure.

[0011] Figure 5 yes Figure 4 A cross-sectional view of the deflector.

[0012] Figures 6A to 6B These are illustrations of different configurations of the deflector and loading port according to some embodiments.

[0013] Figure 6A A first embodiment is shown, wherein the EFEM has two loading ports and two separate deflectors, with one deflector for each loading port.

[0014] Figure 6B A second embodiment is shown, wherein the EFEM has two loading ports and a deflector spanning the width of the two loading ports.

[0015] Figures 7A to 7D This is a plan view of a deflector with a channel having a different cross-sectional shape according to some embodiments.

[0016] Figure 7A The circular cross-section of the channel is shown.

[0017] Figure 7B The hexagonal cross-section of the channel is shown.

[0018] Figure 7C The triangular cross-section of the channel is shown.

[0019] Figure 7D The rectangular cross-section of the channel is shown.

[0020] Figure 8 This is a side sectional view of a second embodiment of the deflector disclosed herein.

[0021] Figure 9 This is a flowchart depicting a method for reducing the relative humidity in a FOUP during use using a deflector, according to some embodiments of the present disclosure.

[0022] Figure 10 This is a flowchart depicting a method for reducing airflow from the EFEM into the FOUP using a deflector, according to some embodiments of the present disclosure.

[0023] Figure 11 A schematic diagram of a wafer process system according to some embodiments of the present disclosure is depicted.

[0024] Figure 12 This is a humidity thermal map of an EFEM with a deflector and FOUP according to some embodiments of the present disclosure. Detailed Implementation

[0025] The following disclosure provides numerous different embodiments or examples for implementing various features of the invention. Specific examples of components and configurations described below are for the purpose of simplifying this disclosure. Of course, these components and configurations are merely examples and are not intended to be limiting. For example, in the following description, forming a first feature above or on a second feature may include embodiments where the first and second features are formed in direct contact, and may also include embodiments where an additional feature may be formed between the first and second features so that the first and second features are not in direct contact. Furthermore, reference numerals and / or letters may be repeated in various instances of this disclosure. This repetition is for simplicity and clarity and does not in itself indicate a relationship between the various embodiments and / or configurations discussed.

[0026] Additionally, for ease of description, spatial relative terms such as “below,” “under,” “lower,” “above,” “upper,” and similar terms are used herein to describe the relationship between one component or feature and another, as illustrated in the figures. Besides the orientations depicted in the figures, spatial relative terms are also intended to cover different orientations of components during use or operation. Devices may be oriented in other ways (rotated 90 degrees or in other orientations), and the spatial relative descriptors used herein shall be interpreted accordingly.

[0027] The numerical values ​​in the specification and claims of this application should be understood to include values ​​that would be identical when reduced to the same number of significant digits, as well as numerical values ​​that differ from those values ​​by experimental error determined using conventional measurement techniques of the type described herein. All scopes disclosed herein include the stated endpoints.

[0028] The term "approximately" can be used to include any numeric value whose basic function can vary without altering its value. When used with a range, "approximately" also discloses a range defined by the absolute values ​​of its two endpoints; for example, "approximately 2 to approximately 4" also discloses a range "from 2 to 4". The term "approximately" can refer to plus or minus 10% of a specified number.

[0029] As used herein, the term "gas" should be interpreted as referring to the gaseous state of a substance, and is not limited to any particular gas. The term "gas" includes, for example, gases with specific properties, such as reactive or non-reactive; ambient air; purified or otherwise modified air; vapor; and so on.

[0030] The term "vertical" is used to indicate an angle of 90° ± 5°.

[0031] This disclosure relates to "laminar flow" and "turbulent flow". Laminar flow is characterized by fluid particles flowing along smooth paths within layers with little mixing between layers. In turbulent flow, fluid particles follow chaotic paths, flow without stratification, and exhibit a high degree of mixing.

[0032] This disclosure relates to a system that can reduce the relative humidity inside the front opening transfer box (FOUP) when the FOUP is installed or loaded onto the device front-end module (EFEM).

[0033] In this regard, semiconductor wafer substrates are processed on many different workstations or process machines during the manufacturing process of integrated circuits. For example, various processing steps, including deposition, cleaning, ion implantation, etching, and protection, can be performed during manufacturing. Front-opening transfer cassettes (FOUPs) are used to store and / or transport one or more semiconductor wafer substrates between various workstations. Wafer substrates need to be protected from contaminants such as particles, organic matter, gases, metals, and water, which can adhere to or adversely affect the desired characteristics of the integrated circuits built upon them; FOUPs can be used for this purpose. Specifically, when the FOUP is closed, its internal space can be purged through the purge inlet and purge outlet. Clean and inert gases (such as nitrogen or clean, dry air) can be pumped into the internal space of the FOUP. A gentle vacuum is used to purge the internal space with ambient air and contaminants contained therein, such as moisture, oxygen, particles, and airborne molecular contaminants.

[0034] Figure 1 A front opening transfer cassette (FOUP) 100 according to some embodiments of the present disclosure is illustrated. The FOUP 100 serves as a storage container and carrier for wafer substrates 102 therein. The FOUP is formed by sidewalls 110 disposed on a base 112 and connected to a cover 114, which together define an internal space 116 for storing a plurality of wafer substrates 102. As seen here, a plurality of slots 120 are formed in the sidewalls 110 of the FOUP 100, and each slot is capable of holding a substrate in a desired position within the internal space of the cassette. The cassette also includes a front door 130 for access to the internal space. The front door may be movable, removable, or detachable from the sidewalls to allow substrates to be transferred in and out of the FOUP. As shown, the front door is moved to one side of the cassette. The size of the FOUP may vary depending on the size of the substrates to be accommodated. In this regard, depending on the generation of tools used, photolithography processes can be performed on wafer substrates with diameters of approximately 200 mm, approximately 300 mm, or approximately 450 mm, and therefore the size of the FOUP will vary.

[0035] The FOUP100 also includes a purge inlet 140 and a purge outlet 142, which are shown herein located on the base of the FOUP. Contaminants in the interior space can be purged when the front door is closed to isolate the interior space of the FOUP from the external environment. An external gas source is connected to the purge inlet, and a vacuum source is connected to the purge outlet.

[0036] Clean gases, such as nitrogen (N2) or clean dry air (CDA), can be introduced into the internal space 116 of the FOUP to remove any contaminants present, whether in the air or deposited on the surfaces of the internal space. The introduction of the clean gas, along with gentle suction through the purge outlet, creates a flow path within the internal space and around any substrate, drawing contaminants out of the internal space. Such contaminants may include chemical residues such as NH3, SO4, F, Cl, NO3, PO4, etc. This provides a clean and safe environment for the wafer substrate contained therein.

[0037] However, the wafer substrate (and the interior space of the FOUP) are easily exposed to moisture, oxygen, particles and other molecular contaminants in the air when the FOUP is opened at a given process tool, because the semiconductor wafer substrate is accessible at this time. Figure 2 This is an external perspective view of a Device Front-End Module (EFEM) 150 according to an embodiment of this disclosure. The EFEM is a structure that is part of an Automated Material Handling System (AMHS) for moving wafer substrates between storage carriers (i.e., FOUPs) and various process modules. The EFEM takes the form of a quad-sided housing 152. The front side 154 of the housing includes one or more loading ports 160. Two loading ports are shown here. Each loading port 160 is configured according to FIMS (Front-Open Interface Mechanical Standard) to receive and approach the contents of the FOUP 100 while protecting the contents from contamination. Handling tools (not shown) are typically coupled to the opposite side of the front side of the EFEM. The top of the housing includes a Filter Fan Unit (FFU) 162, a high-quality unit that provides laminar airflow as an active air curtain to the internal environment of the housing 152. The bottom plate of the EFEM is typically perforated, and downward airflow blows contaminants out of the interior and the EFEM.

[0038] In this respect, the downward air supplied by the FFU (Filter Fan Unit) 162 typically has a much higher relative humidity than the internal environment of the FOUP. For example, the relative humidity of the air inside the EFEM is typically about 40% to about 50%. In contrast, the relative humidity of the air inside the FOUP is typically less than 1%. As a result, when the FOUP is in an open configuration and in fluid communication with the EFEM environment, the FOUP and the wafer substrate inside the FOUP are exposed to the high relative humidity of the EFEM. This humidity, along with exposure to oxygen and moisture, can cause problems for the wafer substrate, such as undesirable oxidation of the copper on the wafer substrate.

[0039] Even when the FOUP front door is open during the cleaning / purging process, the pressure provided by the FFU is higher than the pressure of the cleaning process itself. Furthermore, due to the turbulence generated by the loading port itself, contaminants in the high-humidity laminar airflow provided by the FFU can be blown into the FOUP interior, rather than remaining near the FOUP front door or being blown away through the perforated floor of the EFEM. Additionally, when the FOUP front door is closed again, extra time is required to completely replace the interior space with inert N2 or clean, dry air.

[0040] Therefore, in the systems and methods of this disclosure, a deflector is provided within the EFEM housing. The deflector is used to influence the airflow pattern within the EFEM, particularly by guiding airflow away from the loading port and the FOUP located therein. Multiple holes (or openings) in the body of the deflector serve as guides to direct laminar airflow near the loading port away from and further into the interior of the EFEM housing, while maintaining the laminar nature of the airflow. By redirecting the laminar airflow away from the open FOUP, the increase in relative humidity within the FOUP is reduced.

[0041] Figure 3 This is a side sectional view of an EFEM 150 according to some embodiments of the present disclosure. The internal space 116 of the EFEM housing 152 is in fluid communication with an FFU 162. The FFU typically includes a filter for capturing large particles before one or more fans within the FFU generate laminar airflow or an active air curtain. The FFU is mounted on top of the main housing 152 and generates a laminar airflow 165 (indicated by arrows) that moves downward throughout the internal space. In some embodiments, the relative humidity of the internal space / downward laminar airflow is about 40% to about 50%, and in a particular embodiment about 42%. The velocity of the laminar airflow can be, for example, about 0.03 m / s to about 0.5 m / s, or any other suitable or desired velocity. The downward-flowing gas is discharged into the internal space 116 through a first perforated plate at the top of the housing and exits the EFEM and into the surrounding environment through a second perforated plate at the bottom of the housing.

[0042] Continuing, the front side 154 of housing 152 includes at least one loading port 160. EFEMs with two or four loading ports are known, and any number of loading ports can typically be present. As shown here, a rack 166 is also present, on which the FOUP 100 is placed. The front of the FOUP is connected to the loading port 160, thus providing access to the wafer substrate within the FOUP. The loading port itself includes a door, and the FOUP also includes its own front door. The loading port door is typically opened manually after the FOUP is installed in place. The opening of the FOUP door can be controlled by a computer interface or any other automated process. When the FOUP is open, the interior of the FOUP 100 is in fluid communication with the internal space of the EFEM. This means that the semiconductor wafer substrate stored in the FOUP is exposed to the high relative humidity present in the FFU.

[0043] Still referencing Figure 3 The deflector 200 is fixed to the inner surface 156 of the EFEM main housing 152. The deflector is located above the loading port 160 and below the FFU. The presence of the deflector serves to guide laminar airflow away from the loading port. The deflector itself does not provide active air.

[0044] The deflector can be secured to the inner surface using any known method. For example, in some embodiments, the deflector can be bonded to the EFEM body housing by welding or by using an adhesive. As another example, the EFEM housing is contemplated to include multiple fasteners engaging complementary holes on the deflector. Alternatively, in another embodiment, the rear surface of the deflector may include at least one flange that engages a corresponding groove in the EFEM body housing, for example, by sliding into the groove and holding it in place. This arrangement can also be reversed, with the rear surface of the deflector including a groove that engages with a flange on the EFEM housing.

[0045] Regarding location, in some embodiments, the top of the loading port / FOUP is typically between approximately 1 meter and approximately 5 meters from the bottom of the FFU. In various embodiments, the lower surface of the deflector 200 may be located approximately 0 to approximately 20 centimeters (cm) above the top of the loading port / FOUP. Outside this range, the diverted airflow may have sufficient time to be guided back to the loading port / FOUP.

[0046] Figure 4 and Figure 5 These are rear perspective and side sectional views of a deflector 200 according to some embodiments of the present disclosure. The deflector includes a body 210 having a trapezoidal prism shape and six faces. The upper surface 212 is shorter than the lower surface 214. The body also includes a front surface 216 and an opposing rear surface 218, as well as two side surfaces 220. The front surface 216 is angled relative to the lower surface 214 and is flat or linear.

[0047] It should be noted that when installed in an EFEM, the rear surface is attached to the inner surface of the EFEM housing. The upper surface 212 and the lower surface 214 are substantially perpendicular to the laminar airflow inside the EFEM.

[0048] like Figure 5 As shown, the body also includes multiple channels 230 that extend from the upper surface 212 through the entire body to the lower surface 214. The channels may be straight and extend completely through the body. Figure 4 The visible holes or openings 232 illustrate the cross-sectional shape of the channels. As shown here, the cross-sectional area of ​​each channel 230 has a hexagonal shape. It is expected that all channels will have the same cross-sectional shape within the deflector. For each channel 230, the aperture on the upper surface 212 is close to the rear surface 218, while the aperture on the lower surface 214 is close to the front surface 216. In other words, the channel is at an angle to the rear surface. The channels are also arranged in a matrix to make the most efficient use of the space in the deflector.

[0049] Refer again Figure 5 The cross-sectional view shows a flange 240 extending from the rear surface 218 of the body 210. As previously described, the flange can be used to connect the deflector to the EFEM housing.

[0050] like Figure 4 and Figure 5 As shown, the deflector has a height H measured between the upper surface 212 and the lower surface 214. The height H of the deflector is generally constant between these two surfaces and varies in the portion located between the front surface 216 and the lower surface 214. The deflector has a width W measured between the two sides 220. The width W is generally constant when measured anywhere between the rear surface 218 and the front surface 216. The upper surface 212 has a length L1, and the lower surface 214 has a length L2.

[0051] In a particular embodiment, the height H of the deflector is approximately 2 cm to approximately 15 cm. If the height is too short, the channel will not be able to move the laminar airflow near the loading port to a sufficient distance away from the loading port while maintaining the laminar flow. When the height is too high, note that although the upper surface of the deflector contains holes, laminar airflow still enters the remaining surface and generates turbulence. Laminar flow, not turbulence, is required.

[0052] In a particular embodiment, the length L2 of the lower surface 214 is also approximately 2 centimeters (cm) to approximately 15 centimeters. If the length is too short, the channel will not be able to move the laminar airflow near the loading port a sufficient distance away from the loading port while maintaining the laminar flow. A length of approximately 15 centimeters is sufficient to move the laminar airflow away from the loading port without requiring any additional movement beyond approximately 15 centimeters.

[0053] In a particular embodiment, the length L1 in the upper surface 212 is less than the length L2. Therefore, the laminar airflow is kept away from the loading port, avoiding the generation of turbulence.

[0054] Now for reference Figure 5 The text indicates two angles, θ1 and θ2. The first angle θ1 represents the angle between the lower surface 214 and the front surface 216. In a particular embodiment, the first angle θ1 is approximately 60° to 90°.

[0055] The second angle θ2 represents the angle of the channel within the body and is measured relative to the lower surface 214. In a particular embodiment, the second angle θ2 is also approximately 60° to 90°. Typically, the second angle θ2 is greater than the first angle θ1. It should be noted that the channels 230 in the deflector are all parallel to each other. Therefore, the parallel holes maintain laminar airflow within the interior space of the EFEM housing, guiding intercepted airflow away from the loading port by the same distance. When θ1 and θ2 are less than approximately 60°, the airflow becomes more turbulent and less laminar.

[0056] Next, the channel has a diameter D. In a particular embodiment, the diameter D is approximately 5 millimeters (mm) to approximately 15 millimeters to fit the diameter of the deflector body. Typically, all channels should have the same diameter, but this is not required.

[0057] Figure 6A and Figure 6B These are plan sectional views of two different embodiments of a system including a device front-end module (EFEM) and a deflector. In both figures, the EFEM 150 has two loading ports 160. Two FOUP 100s are adjacent to the loading ports. In both figures, the width of the loading ports is identified by reference numeral 105. The width of the deflector is indicated by the letter W.

[0058] In this regard, the size of the loading port (and FOUP) will vary depending on the size of the wafer substrate it contains. For example, the standard size of a FOUP for a 300mm semiconductor wafer is approximately 420mm wide x 300mm long x 300mm high. Typically, the deflector is large enough to redirect airflow across the entire width of at least one or more loading ports.

[0059] exist Figure 6A In the illustrated embodiment, each loading port 160 has its own deflector 200, or more generally, the number of loading ports is equal to the number of deflectors in the EFEM housing. In such an embodiment, the width W of the deflector can be about 100% to about 120% of the width 105 of the loading port. For example, if the width of the loading port is 420 mm, then the deflector 200 will have a width of about 420 mm to about 504 mm.

[0060] exist Figure 6B In the illustrated embodiment, there is a deflector 200 having a width W sufficient to span the width of the two loading ports 160 and the intermediate distance between the two loading ports. More typically, the deflector may have a width W at least as large as the cumulative width of the loading ports in the EFEM housing.

[0061] The cross-sectional shape of channel 230 in the deflector is not important; the channel can generally have any cross-sectional shape. For example, Figures 7A to 7D The different cross-sectional shapes of the channel and the layout on the upper surface 212 are illustrated in these figures. The inclined front surface 216 is also visible in these figures. Figure 7A A deflector is shown, in which the channel has a circular shape. Figure 7B In the middle, each channel has a hexagonal shape. Figure 7C A channel with a triangular shape is shown. Figure 7D A channel with a rectangular shape is shown.

[0062] Now for reference Figure 7A Each channel 230 has a diameter 225. As previously mentioned, in certain embodiments, the channel diameter is from approximately 5 mm to approximately 15 mm to suit the dimensions of the deflector body. For channels that do not have a circular cross-section, the diameter can be calculated as the equivalent diameter of a circle with the same cross-sectional area as the non-circular channel. If the diameter is less than 5 mm, the flow resistance becomes too high, which may generate turbulence around the deflector. If the diameter is greater than 15 mm, the airflow exiting the deflector will not be laminar.

[0063] Deflectors can be made from conventional materials, such as plastic and / or metal, as needed. The shape and size of the deflector can be modified using conventional manufacturing techniques.

[0064] Figure 8 This is a side sectional view of a second embodiment of the deflector 200 according to a further embodiment of the present disclosure. The main difference in this embodiment is that the front surface 216 is arcuate or curved, rather than as... Figure 5 The flat surface in the embodiment. The curved front surface still maintains laminar airflow. However, the various dimensions and relationships between the different parts of the deflector are the same.

[0065] Figure 9 This is a flowchart illustrating a method for reducing relative humidity in a FOUP during transfer of a semiconductor wafer substrate using the system and deflector described herein, according to embodiments of this disclosure. The method can also be referenced... Figure 3 To better understand, the system includes FOUP100, EFEM150, and deflector 200 within EFEM housing 152.

[0066] First, as shown in the figure, in step S102, FOUP100 is loaded into the loading port 160 of the EFEM. Opening the loading port door of the EFEM is also part of this step.

[0067] In step S104, the FOUP gate is opened, thus exposing the internal wafer substrate to the interior space of the EFEM housing. For example, the wafer substrate may be a wafer made of silicon, germanium arsenide (GaAs), gallium nitride (GaN), or some other suitable material. In a particular embodiment, the method described in this disclosure uses a silicon wafer as the wafer substrate.

[0068] Next, in step S106, a deflector 200 located on the inner surface of the EFEM above the loading port deflects the downward gas 165 generated by the FFU 162 away from the loading port 160. The downward laminar airflow enters the orifice / channel and is guided a short distance away from the opening before the FOUP. The distance the laminar airflow is deflected is determined by the angle of the channel within the deflector 200. Therefore, the high-humidity air from the FFU does not enter the FOUP.

[0069] In step S108, contaminants on the FOUP are purged using a purge gas stream. The purge gas is an inert gas such as N2 or can be clean, dry air. This step typically requires connecting the FOUP to a purge gas source.

[0070] It is worth noting that the relative humidity of the FOUP is typically maintained below 1% when closed. This method allows the relative humidity of the FOUP to be maintained below 25% during door opening and purging. Low relative humidity within the FOUP is an ideal result. In certain embodiments, the relative humidity of the FOUP can be maintained below 20%, below 15%, or below 10%.

[0071] In an additional embodiment of the method, in step S110, the semiconductor wafer substrate is removed from the FOUP for transfer to the process module. In step S112, the FOUP door is then closed. It should be noted that step S108, which involves purging the internal space of the FOUP, can be performed continuously during steps S104, S106, S110, and S112, or it can be performed after step S112.

[0072] Figure 10 This is a flowchart illustrating a method for reducing airflow from the EFEM into the FOUP using the system and deflector described herein, according to embodiments of this disclosure. Similarly, this method also references... Figure 3 The system includes FOUP100, EFEM150, and deflector 200 within EFEM housing 152.

[0073] More typically, in step S202, the deflector 200 is mounted on the inner surface 156 of the EFEM, located above the loading port 160 of the EFEM. The deflector is oriented to guide laminar airflow away from the loading port. As a result, when the FOUP is open, the airflow supplied by the FFU and flowing into the FOUP is reduced compared to an EFEM without such a deflector.

[0074] If necessary, in additional step S204, when the FOUP is connected to the EFEM, the FOUP is purged with a purge gas stream. This is similar to... Figure 9 Step S108. This also reduces the airflow from EFEM into FOUP.

[0075] Now for reference Figure 11 The process system 300 is described. In summary, the process system shown includes EFEM 150 and process module 310. A load locking module 320 is located between EFEM 150 and process module 310.

[0076] As shown in the figure, FOUP100 is also present, located on rack 166 before the loading port of the EFEM. Wafer substrate 102 is present in the FOUP. Deflector 200 is also present in the EFEM, located above the loading port and the FOUP.

[0077] The EFEM also includes a wafer transfer module 330 for the loading port. Typically, the radial, axial, and rotational movements of the wafer transfer module 330 can be coordinated or combined to pick up, transfer, and deliver the wafer substrate 102 between different locations within the process system 300. For example, as shown, the wafer transfer module 330 can be used to transfer the wafer substrate 102 between the FOUP 100 and the loading locking module 320.

[0078] The load locking module 320 can be configured to maintain the atmosphere within the process module 310, for example, if the atmosphere is a high vacuum atmosphere or contains reactive gases for the processing steps. A separate ventilation system 315 for the process module 310 is illustrated here. After the wafer substrate 102 is inserted into one end of the load locking module 320, the door on that end of the load locking module is sealed. The smaller space within the load locking module is then altered to match the atmosphere within the process module 310. The wafer substrate in the load locking module can then be accessed via automated equipment within the process module.

[0079] Process module 310 is typically configured to perform manufacturing processes involving the handling of one or more wafer substrates. In some specific embodiments, the wafer substrate is a multilayer substrate comprising circuitry made of a combination of semiconductor layers, conductive layers, and / or electrically insulating layers. Some examples of processes involving multiple substrates include combinations of wafer substrates with insulating substrates, such as processes for producing silicon-on-insulator (SOI) wafers, silicon-on-sapphire wafers, or silicon-germanium-on-insulator wafers.

[0080] In some embodiments, process module 310 may be configured to perform any manufacturing process or combination of processes on wafer substrate 102. Such manufacturing process may include deposition process, etching process, photolithography process, ion implantation process, thermal processing process, cleaning process, or testing process.

[0081] Non-limiting examples of deposition processes include physical vapor deposition (PVD), chemical vapor deposition (CVD), plasma-enhanced chemical vapor deposition (PECVD), subatmospheric pressure chemical vapor deposition (SACVD), and sputtering. More generally, in deposition processes, one or more atoms are deposited on a wafer substrate to form a thin film with desired properties. Non-limiting examples of etching processes include wet etching, dry etching, and ion beam milling. Typically, etching processes remove material from a wafer substrate at selected locations. In photolithography processes, multiple steps occur. Photoresist is deposited on a wafer substrate and typically spin-dried to form a uniform layer. A photomask, including the desired mask pattern, is exposed via reflective or transmissive exposure to transfer the pattern to the photoresist. The exposed portions of the photoresist are photochemically modified. The photoresist is developed to define openings in the photoresist and expose the layer beneath it. Any or all of these steps can be performed within a process module. In ion implantation, an ion implanter is used to implant various atoms into a silicon lattice, thereby altering the lattice's conductivity at the implantation site to act as a component of a transistor. In thermal processing, the wafer substrate is exposed to high temperatures, such as for annealing specific layers. Cleaning processes remove contaminants or unwanted materials from the substrate surface. Examples of cleaning processes may include multi-step RCA cleaning using H₂SO₄ / H₂O₂, peroxides, hydrofluoric acid, HCl / H₂O₂, and deionized water; degreasing; and plasma treatment. Testing processes include measuring various widths, diameters, and thicknesses, checking for conformity to specifications, and detecting particles or defects on the wafer substrate.

[0082] Figure 12This is a humidity heatmap generated in a simulator. The heatmap includes a FOUP 100 in fluid communication with the internal space of the EFEM housing 152. A deflector 200 is positioned directly above the top surface of the FOUP. Multiple channels 230 through the deflector are visible. High humidity is indicated in white, and low humidity in black. As can be seen from the heatmap, high-humidity air within the EFEM housing is guided away from the FOUP through the holes. This allows the FOUP to maintain a relatively low humidity level inside. In some embodiments, the relative humidity in the FOUP 106 is approximately 25% or lower.

[0083] Therefore, some embodiments of this disclosure relate to a processing system that transfers a semiconductor wafer substrate to a processing module. The system includes a device front-end module (EFEM) and a process module. The EFEM has at least one loading port on one side and a fan filter unit (FFU) on its top, which generates a downward laminar airflow within the EFEM. At least one deflector is located on the inner surface of the EFEM above the at least one loading port. The at least one deflector guides the laminar airflow away from the at least one loading port. The deflector includes a body with an inclined or curved front surface, a rear surface adjacent to the inner surface of the EFEM, and a plurality of parallel channels extending from the upper surface of the body to the lower surface of the body at an angle to the upper surface. The process module is configured to receive the semiconductor wafer substrate from the EFEM when a front-opening transfer cassette (FOUP) containing the semiconductor wafer substrate is loaded at the at least one loading port.

[0084] In some embodiments, the width of the body is about 100% to about 120% of the width of the at least one loading port.

[0085] In some embodiments, the device front-end module has a plurality of loading ports, and the at least one deflector has a width sufficient to span two loading ports.

[0086] In some embodiments, the diameter of the channel is from about 5 mm to about 15 mm.

[0087] In some embodiments, the channel is at an angle of about 60° to about 90° relative to the lower surface.

[0088] In some embodiments, the channel has a triangular, rectangular, hexagonal, or circular cross-section.

[0089] In some embodiments, the upper and lower surfaces of the body are substantially perpendicular to the laminar airflow within the device front-end module.

[0090] In some embodiments, the at least one deflector is located at a position between 0 and 20 cm above the at least one loading port.

[0091] In some embodiments, the at least one deflector is positioned at a distance of about 1 meter to about 5 meters from the bottom of the fan filter unit.

[0092] In some embodiments, the at least one deflector includes a flange extending from the rear surface of the body, the flange engaging a slot in the front-end module of the device.

[0093] In some embodiments, the number of the at least one deflector is equal to the number of the at least one loading port.

[0094] In some embodiments, the laminar airflow in the device front-end module has a relative humidity of about 40% to about 50%.

[0095] In some embodiments, the process module is configured to perform a deposition process, an etching process, a photolithography process, an ion implantation process, a heat treatment process, a cleaning process, or a testing process.

[0096] Other embodiments of this disclosure relate to a method for reducing relative humidity in a front-opening transfer cassette (FOUP) during the transfer of a semiconductor wafer substrate. The FOUP is loaded at the loading port of a device front-end module (EFEM). The FOUP door is opened. Downward gas generated by a fan filter unit is deflected away from the loading port using a deflector located on the inner surface of the device front-end module above the loading port. The deflector includes a body having an angled or curved front surface, a rear surface adjacent to the inner surface of the device front-end module, and a plurality of parallel channels extending from an upper surface of the body to a lower surface of the body angled to the upper surface. Furthermore, the interior of the FOUP is purged with a purge gas stream.

[0097] In some embodiments, the downward gas has a relative humidity of about 40% to about 50%, the front opening conveyor box has a relative humidity of less than 1% before the door is opened, and the front opening conveyor box maintains a relative humidity of less than 25% during purging.

[0098] In some embodiments, the front surface and the channel are each angled relative to the lower surface, and the angle between the channel and the lower surface is greater than the angle between the lower surface and the front surface.

[0099] In some embodiments, the method further includes: removing a semiconductor wafer substrate from the front-opening transfer box; and closing the door of the front-opening transfer box.

[0100] Various embodiments also disclose a method for reducing airflow from a device front-end module (EFEM) into a front-opening transfer box (FOUP) during the transfer of a semiconductor wafer substrate. For this purpose, a deflector is mounted on an inner surface above the loading port of the EFEM so that the deflector guides laminar airflow away from the loading port. The deflector includes a body having an inclined or curved front surface, a rear surface adjacent to the inner surface of the device front-end module, and a plurality of parallel channels extending from an upper surface of the body to a lower surface of the body angled to the upper surface.

[0101] In some embodiments, the front-opening conveyor box is further purged with a purge gas stream.

[0102] In some embodiments, the width of the deflector is about 100% to about 120% of the width of the loading port.

[0103] The foregoing outlines features of several embodiments to enable those skilled in the art to better understand the nature of this disclosure. Those skilled in the art will understand that this disclosure can be readily used as a basis for designing or modifying other processes and structures for performing the same purposes and / or achieving the same advantages of the embodiments introduced herein. Those skilled in the art will also recognize that such equivalent constructions do not depart from the spirit and scope of this disclosure, and that various changes, substitutions, and modifications can be made herein without departing from the spirit and scope of this disclosure.

Claims

1. A system for transferring a semiconductor wafer substrate to a process module, characterized in that, include: The device front-end module has at least one loading port on its side and a fan filter unit on its top, the fan filter unit generating a downward laminar airflow within the device front-end module; At least one deflector, located on the inner surface of the device front-end module above the at least one loading port and below the fan filter unit, is used to guide the laminar airflow away from the at least one loading port. The at least one deflector includes a body having an inclined or curved front surface, a rear surface adjacent to the inner surface of the device front-end module, and a plurality of parallel channels extending from an upper surface of the body to a lower surface of the body at an angle to the rear surface. The at least one deflector includes a flange extending from the rear surface of the body, the flange engaging a slot in the device front-end module. as well as A process module is configured to receive the semiconductor wafer substrate from the device front-end module when a front-opening transfer box containing the semiconductor wafer substrate is loaded at at least one loading port.

2. The system of claim 1, wherein the width of the body is 100% to 120% of the width of the at least one loading port.

3. The system of claim 1, wherein the device front-end module has a plurality of loading ports, and the at least one deflector has a width sufficient to span two loading ports.

4. The system according to claim 1, wherein the diameter of the channel is 5 mm to 15 mm.

5. The system of claim 1, wherein the channel is at an angle between 60° and 90° relative to the lower surface.

6. The system of claim 1, wherein the channel has a triangular, rectangular, hexagonal, or circular cross-section.

7. The system of claim 1, wherein the upper and lower surfaces of the body are substantially perpendicular to the laminar airflow within the device front-end module.

8. The system of claim 1, wherein the at least one deflector is located at a position between 0 and 20 cm above the at least one loading port.

9. The system of claim 1, wherein the at least one deflector is positioned 1 to 5 meters from the bottom of the fan filter unit.

10. The system of claim 1, wherein the number of the at least one deflector is equal to the number of the at least one loading port.

11. The system of claim 1, wherein the laminar airflow in the device front-end module has a relative humidity of 40% to 50%.

12. The system of claim 1, wherein the process module is configured to perform a deposition process, an etching process, a photolithography process, an ion implantation process, a heat treatment process, a cleaning process, or a testing process.

13. A method for reducing relative humidity in a front-opening transfer box, the method being used during semiconductor wafer substrate transfer, characterized in that, include: Load the front-opening transfer box at the loading port of the front-end module of the equipment; Open the door of the front-opening conveyor box; A deflector on the inner surface of the device front-end module located above the loading port is used to deflect the downward gas generated by the fan filter unit away from the loading port. The deflector includes a body having an inclined or curved front surface, an upper surface, a lower surface, a rear surface adjacent to the inner surface of the device front-end module, and a plurality of parallel channels extending from the upper surface of the body through the body to the lower surface at an angle to the rear surface. as well as The front-opening conveyor box is purged with a stream of purging gas.

14. The method of claim 13, wherein the downward gas has a relative humidity of 40% to 50%, the front-opening conveyor box has a relative humidity of less than 1% before the door is opened, and the front-opening conveyor box maintains a relative humidity of less than 25% during purging.

15. The method of claim 13, wherein the front surface and the channel are each angled relative to the lower surface, and the angle between the channel and the lower surface is greater than the angle between the lower surface and the front surface.

16. The method of claim 13, further comprising: Remove the semiconductor wafer substrate from the front-opening transfer box; and close the door of the front-opening transfer box.

17. A method for reducing airflow from a device front-end module into a front-opening transfer box, the method being used during semiconductor wafer substrate transfer, characterized in that, include: A deflector is installed on the inner surface of the device front-end module above the loading port, wherein the deflector guides laminar airflow away from the loading port. The deflector includes a body having an inclined or curved front surface, a rear surface adjacent to the inner surface of the device front-end module, and a plurality of parallel channels extending from the upper surface of the body through the body to a lower surface of the body at an angle to the rear surface.

18. The method of claim 17, further comprising purging the front-opening conveyor box with a purge gas stream.

19. The method of claim 17, wherein the width of the deflector is 100% to 120% of the width of the loading port.

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