Extreme ultraviolet source, method for improving asymmetric deposition, and radiation source

Abstract

An extreme ultraviolet source, a method for improving asymmetric deposition, and a radiation source, wherein a control system includes a plurality of pressure sensors, each of which detects the pressure in a corresponding dynamic airlock nozzle control zone of a plurality of dynamic airlock nozzle control zones. Each dynamic airlock nozzle control zone includes one or more dynamic airlock nozzles. The control system includes a plurality of mass flow controllers. Each of the plurality of mass flow controllers controls the flow rate in a corresponding dynamic airlock nozzle control zone of the plurality of dynamic airlock nozzle control zones. The control system includes a controller to selectively cause one or more of the plurality of mass flow controllers to adjust the flow rate in one or more dynamic airlock control zones of the plurality of dynamic airlock nozzle control zones according to the pressure detected by the plurality of pressure sensors in the dynamic airlock control zones of the plurality of dynamic airlock nozzle control zones.

Description

Technical Field

[0001] Embodiments of the present disclosure relate to extreme ultraviolet sources, methods of improving asymmetric deposition, and radiation sources. Background Art

[0002] An extreme ultraviolet (EUV) source may use a laser to generate EUV light to excite particles, such as tin (Sn) particles. In operation, the laser excites the particles to generate a Sn-based plasma that emits light in the desired EUV radiation wavelength range. The dynamic gas lock (DGL) of the intermediate focus (IF) cover is a particle collector that is used to prevent particles from escaping the chamber of the EUV source and entering the EUV scanner (which could otherwise cause damage to the reticles / reticles in the EUV scanner). Summary of the invention

[0003] Some embodiments described herein provide an extreme ultraviolet source. This extreme ultraviolet source includes a plurality of dynamic airlock nozzles. This extreme ultraviolet source includes a plurality of pressure sensors, wherein each of the plurality of pressure sensors detects the pressure in a corresponding dynamic airlock nozzle control zone in a plurality of dynamic airlock nozzle control zones, wherein each dynamic airlock nozzle control zone includes a different set of dynamic airlock nozzles from a plurality of dynamic airlock nozzles, wherein each of the plurality of pressure sensors is configured at a different dynamic airlock nozzle in a plurality of dynamic airlock nozzles. This extreme ultraviolet source includes a plurality of mass flow controllers (MFCs), wherein each of the plurality of mass flow controllers controls the flow rate in a corresponding dynamic airlock nozzle control zone in a plurality of dynamic airlock nozzle control zones, wherein each of the plurality of mass flow controllers is associated with a different dynamic airlock nozzle control zone in a plurality of dynamic airlock nozzle control zones. This extreme ultraviolet source includes a plurality of manifolds, wherein each manifold connects a different dynamic airlock nozzle control zone in a plurality of dynamic airlock nozzle control zones.

[0004] Some embodiments described herein provide a method for improving asymmetric deposition. The method includes receiving a plurality of signals from a plurality of pressure sensors through a controller associated with a radiation source, each of the plurality of signals indicating a corresponding pressure detected by a corresponding pressure sensor of the plurality of pressure sensors. The method includes determining, through the controller and based on the plurality of signals, that one of a plurality of dynamic airlock nozzles of an intermediate focus cover is at least partially blocked. The method includes, based on determining that the dynamic airlock nozzle is at least partially blocked, causing one or more of a plurality of mass flow controllers to adjust a flow rate in one or more of a plurality of dynamic airlock nozzle control zones through the controller, wherein the at least partially blocked dynamic airlock nozzle is included in one of the plurality of dynamic airlock nozzle control zones, wherein each of the plurality of mass flow controllers is associated with a corresponding dynamic airlock nozzle control zone of the plurality of dynamic airlock nozzle control zones.

[0005] Some embodiments described herein provide a radiation source. The radiation source includes a plurality of pressure sensors, wherein each of the plurality of pressure sensors is disposed at a corresponding dynamic airlock nozzle of a plurality of dynamic airlock nozzles of an intermediate focus cover, wherein each of the plurality of pressure sensors provides a signal indicating a corresponding pressure at a corresponding dynamic airlock nozzle of the plurality of dynamic airlock nozzles. The radiation source includes a plurality of mass flow controllers, wherein each of the plurality of mass flow controllers controls a flow rate in a corresponding dynamic airlock nozzle control zone of a plurality of dynamic airlock nozzle control zones, wherein each dynamic airlock nozzle control zone is associated with a corresponding subset of dynamic airlock nozzles from the plurality of dynamic airlock nozzles. The radiation source includes a plurality of manifolds, wherein each of the plurality of manifolds provides fluid to a corresponding dynamic airlock nozzle control zone of the plurality of dynamic airlock nozzle control zones. BRIEF DESCRIPTION OF THE DRAWINGS

[0006] The following detailed description is best understood when read in conjunction with the accompanying drawings. It should be noted that, in accordance with standard industry practice, various features are not drawn to scale. In fact, the size of various features may be increased or decreased as desired to make the discussion clear.

[0007] Figure 1 is a schematic diagram illustrating an embodiment of a radiation source;

[0008] FIG. 2A to FIG. 2D is a schematic diagram illustrating one embodiment of a control system associated with a dynamic air lock for an intermediate focus cover and associated with controlling a flow rate at a dynamic air lock nozzle as described herein;

[0009] FIG. 3A to FIG. 3Cis a schematic diagram illustrating an embodiment of operations performed by a control system as described herein in connection with reducing or preventing particulate accumulation;

[0010] Figure 4 is a schematic diagram illustrating an embodiment of dividing the pressure sensors of the control system into a plurality of sensor groups;

[0011] FIG. 5A to FIG. 5E is a schematic diagram illustrating additional embodiments of the intermediate focus cover and control system described herein;

[0012] Figure 6 is a schematic diagram illustrating an embodiment of components of one or more devices of a control system;

[0013] Figure 7 is a flow chart illustrating an embodiment of a process for improving control of flow rate at a dynamic airlock nozzle of an intermediate focus cover;

[0014] Figure 8 is a schematic diagram illustrating one embodiment of a lithography system described herein.

[0015]

Explanation of symbols

[0016] 100: Radiation source

[0017] 102: Cavity

[0018] 104: Concentrator

[0019] 106: Middle focus cap

[0020] 106w: tapered wall

[0021] 110: Dynamic air lock nozzle

[0022] 112: Dynamic air lock nozzle

[0023] 114: Dynamic air lock nozzle

[0024] 116: Fluid channel

[0025] 116a: Fluid channel

[0026] 116b: Second fluid channel

[0027] 116c: Third fluid channel

[0028] 116d: Fourth fluid channel

[0029] 118: Fluid channel

[0030] 150:Laser beam

[0031] 152: Target materials, source materials

[0032] 154: Plasma

[0033] 156: Plasma Emission

[0034] 158: Radiation

[0035] 160: Fluid

[0036] 200: Control system

[0037] 202: Pressure sensor

[0038] 202a: Pressure sensor

[0039] 202a1: Pressure Sensor

[0040] 202a2: Pressure Sensor

[0041] 202a3: Pressure Sensor

[0042] 202a4: Pressure Sensor

[0043] 202a5: Pressure Sensor

[0044] 202a6: Pressure Sensor

[0045] 202a7: Pressure Sensor

[0046] 202a8: Pressure Sensor

[0047] 202b: Pressure sensor

[0048] 202b1: Pressure sensor

[0049] 202b2: Pressure sensor

[0050] 202b3: Pressure sensor

[0051] 202b4: Pressure sensor

[0052] 202b5: Pressure sensor

[0053] 202b6: Pressure Sensor

[0054] 202b7: Pressure Sensor

[0055] 202b8: Pressure Sensor

[0056] 202c1: Pressure sensor

[0057] 202c2: Pressure sensor

[0058] 202c3: Pressure sensor

[0059] 202c4: Pressure sensor

[0060] 202d1: Pressure sensor

[0061] 202d2: Pressure sensor

[0062] 202d3: Pressure sensor

[0063] 202d4: Pressure sensor

[0064] 204: Manifold

[0065] 204a: Manifold

[0066] 204b: Manifold

[0067] 204c: Manifold

[0068] 204d: Manifold

[0069] 204e: Manifold

[0070] 204f: Manifold

[0071] 204g: Manifold

[0072] 204h: Manifold

[0073] 206:Mass Flow Controller

[0074] 206a: Mass flow controller

[0075] 206b: Mass flow controller

[0076] 206c: Mass flow controller

[0077] 206d: Mass Flow Controller

[0078] 206e: Mass Flow Controller

[0079] 206f: Mass Flow Controller

[0080] 206g: Mass Flow Controller

[0081] 206h: Mass flow controller

[0082] 208: Controller

[0083] 210: Dynamic air lock nozzle control area

[0084] 210a: Dynamic air lock nozzle control area

[0085] 210b: Dynamic air lock nozzle control area

[0086] 210c: Dynamic air lock nozzle control area

[0087] 210d: Dynamic air lock nozzle control area

[0088] 210e: Dynamic air lock nozzle control area

[0089] 210f: Dynamic air lock nozzle control area

[0090] 210g: Dynamic air lock nozzle control area

[0091] 210h: Dynamic air lock nozzle control area

[0092] 212: Water collection equipment

[0093] 300:Example

[0094] 302: Reference number

[0095] 304: Reference number

[0096] 306: Reference number

[0097] 600: Device

[0098] 610: Bus

[0099] 620: Processor

[0100] 630: Memory

[0101] 640: Storage Components

[0102] 650: Input component

[0103] 660: Output Component

[0104] 670: Communication Components

[0105] 700: Process

[0106] 710: Block

[0107] 720: Block

[0108] 730: Block

[0109] 800: Lithography System

[0110] 802: Exposure machine

[0111] 804: Shrink mask

[0112] 806:Semiconductor substrate

[0113] 808: Middle focus

[0114] 810: Droplet generator head

[0115] 812: Illuminator

[0116] 814: Projection optical instrument box

[0117] 816: Substrate Platform

[0118] 818a: Reflector

[0119] 818b: Reflector

[0120] 820: Reflector

[0121] 822a: Reflector

[0122] 822b: Reflector

[0123] 822c: Reflector

[0124] 822d: Reflector

[0125] 822e: Reflector

[0126] 822f: Reflector DETAILED DESCRIPTION

[0127] The following disclosure provides many different embodiments or examples to implement different features of the subject matter provided. Specific examples of components and arrangements are described below to simplify the disclosure. These are of course only examples and are not intended to be limiting. For example, in the description, forming a first feature on a second feature may include an embodiment in which the first feature and the second feature are formed in direct contact, and may also include an embodiment in which an additional feature is formed between the first feature and the second feature, so that the first feature and the second feature may not be in direct contact. In addition, the disclosure may repeat reference symbols and / or letters in multiple examples. This repetition is for the purpose of simplicity and clarity and does not inherently define the relationship between the multiple embodiments and / or configurations discussed.

[0128] Additionally, spatially relative terms, such as "beneath," "below," "lower," "above," "upper," and the like, may be used herein to concisely describe the relationship of one element or feature to another element or features as depicted in the accompanying drawings. These spatially relative terms are intended to encompass different orientations of the elements in use or operation in addition to the orientation depicted in the figures. The device may be otherwise oriented (rotated 90 degrees or at other orientations) and the spatially relative descriptors used herein interpreted accordingly.

[0129] In the operation of a radiation source, such as an extreme ultraviolet source, flow separation can cause turbulence and eddies to form on the conical wall of the dynamic airlock of the intermediate focus cover. If there is an asymmetric particle deposition on the conical wall, this asymmetric particle deposition triggers early flow separation and generates relatively more violent eddies. This relatively more violent eddies increase the accumulation rate of particles on the conical wall, which makes the conical flow direction become asymmetric. The asymmetry of the conical flow then causes further asymmetric particle deposition on the conical wall. Particle deposition on the conical wall can cause at least partial blockage of the nozzle of the dynamic airlock. Partial blockage of the dynamic airlock nozzle increases the flow rate from the dynamic airlock nozzle, which worsens the asymmetry of the flow and increases the particle accumulation rate at the blockage location. As the particle accumulation becomes thicker, the accumulated particles are heated by light and released from the conical wall. The released tin particles can move from the cavity of the radiation source to the scanner. The gas in the scanner carries the tin particles (which can bounce off several mirrors in the scanner) to the doubling mask, and the tin particles can adhere to the doubling mask. Tin particles on the reticle can cause reticle defects, which can reduce pattern quality and wafer yield, or even damage the scanner.

[0130] Currently, the dynamic airlock of the intermediate focus cover has three rows of dynamic airlock nozzles, with the first and second rows exposed to the chamber environment. Here, all the dynamic airlock nozzles of the first and second rows are supplied through the same fluid channel, which means that all the dynamic airlock nozzles of the first and second rows are controlled together, and it is not possible to individually adjust the flow rate of a subset of the dynamic airlock nozzles in a given row. In addition, there is no mechanism to detect the flow rate at the dynamic airlock nozzles so as to be able to detect the blockage of a given dynamic airlock nozzle.

[0131] Some aspects described herein provide control systems and techniques and apparatus for dynamic airlocks (of intermediate focus caps) capable of reducing or preventing asymmetric particle (e.g., tin particles) deposition on the conical wall of a dynamic airlock. In some embodiments, asymmetric deposition can be reduced or prevented by improving flow rate control at a dynamic airlock nozzle of a dynamic airlock. For example, in some embodiments, a dynamic airlock nozzle is divided into a plurality of dynamic airlock control zones (e.g., four dynamic airlock nozzle control zones), and the flow rate in each dynamic airlock nozzle control zone is controlled by an independent mass flow controller (MFC) (e.g., the flow rate in each dynamic airlock nozzle control zone can be controlled by a different mass flow controller). In some embodiments, the control system is capable of determining the flow rate at the dynamic airlock nozzle to determine whether a given dynamic airlock nozzle in a given dynamic airlock nozzle control zone is at least partially blocked due to particle deposition. In some embodiments, the control system includes one or more pressure sensors (e.g., mounted in or near one or more airlock nozzles in each airlock nozzle control zone) for determining the flow rate (e.g., based on the pressure detected by the pressure sensor). Additional details about the control system are provided below.

[0132] In some embodiments, the techniques and apparatus described herein reduce or prevent particle deposition on the conical walls, which reduces the likelihood of particles moving from the radiation source toward the reticle to the scanner, thereby reducing the likelihood of defects, which means that pattern quality and wafer yield can be improved, and damage to the scanner can be prevented.

[0133] Figure 1 is a schematic diagram illustrating an embodiment of a radiation source 100. The radiation source 100 may be, for example, an extreme ultraviolet source. Figure 1 As shown, the radiation source 100 includes a cavity 102, a concentrator 104, and an intermediate focus cover 106 having a tapered wall 106w. It should be noted that the radiation source 100 includes other components and features, which are not shown for the purpose of clarity. Figure 1 Other components and features of the radiation source 100 may include, for example, a laser source, a beam delivery system, a focusing lens, a droplet generator, a droplet collector, one or more exhaust ports, one or more blades, one or more grooves, or one or more exhaust ports, to name a few.

[0134] The radiation source 100 utilizes laser produced plasma (LPP) to generate light (e.g., extreme ultraviolet light). In operation, a laser source, such as a pulsed carbon dioxide (CO2) laser, generates a laser beam 150. As shown, the laser beam 150 is provided (e.g., via a beam delivery system to a focusing lens) so that the laser beam 150 is focused through a window of a condenser 104. The laser beam 150 is focused onto a target material 152 (e.g., tin droplets provided by a droplet generator), which generates a plasma 154. The plasma 154 generates plasma emissions 156, some of which are radiation 158. As shown, the condenser 104 reflects the radiation 158 and focuses it through the cavity 102 toward an opening of the intermediate focus cap 106 (e.g., for use in a lithography exposure process).

[0135] The intermediate focus cover 106 is a component that provides an intermediate focus for the radiation 158. In some embodiments, a dynamic air lock is integrated into the intermediate focus cover 106. The dynamic air lock of the intermediate focus cover 106 is used to prevent the material in the cavity 102 from leaving the cavity 102. For example, Figure 1 As shown, in order to prevent fluid, particles, droplets, or another type of material present in the environment of the chamber 102 from leaving the chamber 102 (e.g., to prevent particles or droplets from moving to the scanner), the dynamic airlock injects a fluid 160 (e.g., hydrogen gas (H2)) through a set of dynamic airlock nozzles in a direction away from the opening of the intermediate focus cover 106. In some embodiments, the flow rate at the dynamic airlock nozzles is controlled by a control system. Additional details regarding the intermediate focus cover 106 with integrated dynamic airlock nozzles and the control system related to controlling the flow rate at the dynamic airlock nozzles are described below.

[0136] As shown above, Figure 1 Provided as an example. Other examples may differ from the Figure 1 described. Figure 1 The number and arrangement of components shown in the figure are provided as an example. Figure 1 The components shown may have additional components, fewer components, different components, or a different arrangement of components.

[0137] FIG. 2A to FIG. 2D is a schematic diagram illustrating one embodiment of a control system 200 associated with a dynamic airlock of an intermediate focus cover 106 and associated with controlling flow rates of a number of dynamic airlock nozzles as described herein.

[0138] like Figure 2A and Figure 2B As shown, the intermediate focus cover 106 includes a dynamic air lock nozzle 110 (e.g., a first row of dynamic air lock nozzles), a dynamic air lock nozzle 112 (e.g., a second row of dynamic air lock nozzles), and a dynamic air lock nozzle 114 (e.g., a third row of dynamic air lock nozzles, not shown). Figure 2B ). In some embodiments, as shown, each group of dynamic airlock nozzles is arranged around the circumference of the opening of the intermediate focus cover 106 at different locations on the tapered wall 106w of the intermediate focus cover 106. In some embodiments, each row of dynamic airlock nozzles 110 has a number of dynamic airlock nozzles that can be partitioned into multiple control zones. For example, the intermediate focus cover 106 may include 16 dynamic airlock nozzles in a given row, so that each row can be divided into four zones. In some embodiments, the size of the outlet of a given dynamic airlock nozzle 110 (e.g., dynamic airlock nozzle 110, dynamic airlock nozzle 112, or dynamic airlock nozzle 114) can be about 1 mm (e.g., 1.1 mm). In some embodiments, the intermediate focus cover 106 may include a different number of dynamic air lock nozzle holes (e.g., less than 16, or more than 16) and / or dynamic air lock nozzle holes having a size other than approximately 1 mm (e.g., less than 1.1 mm, or greater than 1.1 mm), depending on the design and / or size constraints of the intermediate focus cover 106.

[0139] In some embodiments, fluid is supplied to a subset of dynamic airlock nozzles 110 and a subset of dynamic airlock nozzles 112 through different fluid channels 116. For example, Figure 2A and Figure 2B As shown, the fluid 160 may be supplied to the first subset of the dynamic airlock nozzles 110 and the first subset of the dynamic airlock nozzles 112 through the fluid channel 116a, the fluid 160 may be supplied to the second subset of the dynamic airlock nozzles 110 and the second subset of the dynamic airlock nozzles 112 through the second fluid channel 116b, the fluid 160 may be supplied to the third subset of the dynamic airlock nozzles 110 and the third subset of the dynamic airlock nozzles 112 through the third fluid channel 116c, and the fluid 160 may be supplied to the fourth subset of the dynamic airlock nozzles 110 and the fourth subset of the dynamic airlock nozzles 112 through the fourth fluid channel 116d. Here, each fluid channel 116 is separated from each other fluid channel 116. Figure 2C 1 is a conceptual diagram illustrating the separation of the fluid channels 116 in connection with supplying the fluid 160 to different subsets of the dynamic airlock nozzles 110 and the dynamic airlock nozzles 112. It should be noted that the fluid 160 is supplied to the dynamic airlock nozzles 114 through the fluid channels 118 (e.g., the fluid may be supplied to each dynamic airlock nozzle 114 through a single fluid channel 118 that is separate from the fluid channels 116), as shown in FIG. Figure 2A shown.

[0140] In some embodiments, Figure 2BAs shown, a specific subset of dynamic airlock nozzles 110 and a specific subset of dynamic airlock nozzles 112 are included in a specific dynamic airlock nozzle control zone 210 utilized by the control system 200. For example, in Figure 2B In the illustrated embodiment, a first subset of the four dynamic airlock nozzles 110 and a first subset of the four dynamic airlock nozzles 112 are included in a dynamic airlock nozzle control zone 210a, a second subset of the four dynamic airlock nozzles 110 and a second subset of the four dynamic airlock nozzles 112 are included in a dynamic airlock nozzle control zone 210b, a third subset of the four dynamic airlock nozzles 110 and a third subset of the four dynamic airlock nozzles 112 are included in a dynamic airlock nozzle control zone 210c, and a fourth subset of the four dynamic airlock nozzles 110 and a fourth subset of the four dynamic airlock nozzles 112 are included in a dynamic airlock nozzle control zone 210d.

[0141] In some embodiments, each dynamic air lock nozzle control zone 210 includes the same number of dynamic air lock nozzles. Figure 2B As shown, each of the dynamic airlock nozzle control zone 210a, the dynamic airlock nozzle control zone 210b, the dynamic airlock nozzle control zone 210c, and the dynamic airlock nozzle control zone 210d includes four dynamic airlock nozzles 110 and four dynamic airlock nozzles 112. In some embodiments, having an equal number of dynamic airlock nozzles across the dynamic airlock nozzle control zone 210 can control the flow field by improving flow uniformity. In some embodiments, as described below, the controller 208 of the control system 200 can independently control the flow rate in each of the dynamic airlock nozzle control zones 210 (for example, to reduce or prevent clogging of one or more dynamic airlock nozzles).

[0142] In some embodiments, the control system 200 includes at least two dynamic air lock nozzle control zones 210. For example, Figure 2B As shown, in some embodiments, the control system 200 may include four dynamic airlock nozzle control zones 210. In general, the control system 200 may include any number of dynamic airlock nozzle control zones more than one. It should be noted that a higher number of dynamic airlock nozzle control zones 210 can improve flow field control by providing relatively finer control over the injection of the fluid 160. Conversely, a lower number of dynamic airlock nozzle control zones 210 reduces the complexity and cost of the control system 200 by reducing the number of components in the control system 200, thereby simplifying the manufacturability and configuration of the control system 200. Alternative examples of configurations of the dynamic airlock nozzle control zones 210 are described below.

[0143] like Figure 2A and Figure 2BAs further shown, the control system 200 includes a group of pressure sensors 202a and 202b, a group of manifolds 204 , a group of mass flow controllers (MFCs) 206 , and a controller 208 .

[0144] The pressure sensor 202 is a component capable of detecting the amount of pressure at the pressure sensor 202 and providing a signal indicative of the pressure at the pressure sensor 202. In other words, the pressure sensor 202 is a device that generates and provides a signal having a level that is a function of the pressure at the pressure sensor 202. In some embodiments, the pressure sensor 202 can communicate with the controller 208 (e.g., via a wired connection or a wireless connection).

[0145] In some embodiments, Figure 2A and Figure 2B As shown, the pressure sensor 202 is arranged at or near the dynamic airlock nozzle 110. That is, in some embodiments, the pressure sensor 202 is arranged at a dynamic airlock nozzle in the first column of dynamic airlock nozzles of the intermediate focus cover 106. The pressure sensor 202 is configured to monitor the inlet flow from the dynamic airlock nozzle 110. In some embodiments, the arrangement of the pressure sensor 202 at the dynamic airlock nozzle 110 (rather than at the dynamic airlock nozzle 112 or the dynamic airlock nozzle 114) improves the detection of dynamic airlock nozzle blockage because the blockage is more likely to occur at the dynamic airlock nozzle 110 than at the dynamic airlock nozzle 112 or the dynamic airlock nozzle 114.

[0146] In some embodiments, Figure 2B As shown, the pressure sensor 202 is installed at each dynamic air lock nozzle 110 of the intermediate focus cover 106. For example, as shown, the pressure sensor 202a1, the pressure sensor 202a2, the pressure sensor 202a3, and the pressure sensor 202a4 may be installed in the dynamic air lock nozzle control area 210a, the pressure sensor 202b1, the pressure sensor 202b2, the pressure sensor 202b3, and the pressure sensor 202b4 may be installed in the dynamic air lock nozzle control area 210b, the pressure sensor 202c1, the pressure sensor 202c2, the pressure sensor 202c3, and the pressure sensor 202c4 may be installed in the dynamic air lock nozzle control area 210c, and the pressure sensor 202d1, the pressure sensor 202d2, the pressure sensor 202d3, and the pressure sensor 202d4 may be installed in the dynamic air lock nozzle control area 210d. Alternative examples of arrangements of pressure sensors 202 are described below.

[0147] The manifold 204 includes one or more water intake devices (e.g., pipes, conduits, rafts, and / or the like) through which the fluid 160 is provided to the fluid channel 116 for injection through the one or more dynamic air lock nozzles 110 and the one or more dynamic air lock nozzles 112. It should be noted that in some embodiments, a given manifold 204 supplies fluid 160 to only one fluid channel 116, and a different water supply and drainage device (e.g., another manifold, not shown) may also be used to supply fluid 160 to the fluid channel 116. Figure 2A and Figure 2B ) supplies fluid 160 to fluid channel 118.

[0148] In some embodiments, the control system 200 includes a group of manifolds 204, wherein each manifold 204 is associated with a different dynamic airlock nozzle control zone 210. For example, Figure 2B As shown, the control system 200 may include four manifolds 204 - a manifold 204a associated with the dynamic airlock nozzle control zone 210a, a manifold 204b associated with the dynamic airlock nozzle control zone 210b, a manifold 204c associated with the dynamic airlock nozzle control zone 210c, and a manifold 204d associated with the dynamic airlock nozzle control zone 210d.

[0149] In some embodiments, the manifolds 204 of the control system 200 are equidistant manifolds, meaning that in a group of manifolds 204, the distance of the path of the fluid 160 flowing through the manifolds 204 (e.g., to the outlet of the manifold 204) is substantially the same. In some embodiments, the use of equidistant manifolds 204 can improve the uniformity of the flow field. For example, it is desirable to prevent or minimize the difference in pressure and flow rate between the dynamic airlock nozzles of the intermediate focus cover 106. According to fluid mechanics theory, as the length of the conduit increases, the friction between the fluid and the tube wall increases the pressure drop. Therefore, the longer the path, the greater the pressure loss. Also with respect to the White-nosed equation, a change in pressure in the flow field changes the flow rate. Here, the equidistant manifolds 204 reduce or eliminate the difference in pressure loss between the manifolds 204, thereby improving the distribution of the flow field in the cavity 102. Figure 2D is a schematic diagram illustrating an example of an equidistant manifold 204. Figure 2D As shown, the fluid 160 is provided to the manifolds 204a to 204d by a water extraction device 212 (e.g., a conduit, a tube, or the like). As shown, the lengths of the manifolds 204a to 204d can be substantially the same, meaning that the distance of the path of the fluid 160 flowing through the manifolds 204 (e.g., to the outlet of the manifold 204 at the mass flow controller 206) is substantially the same in the group of manifolds 204.

[0150] Please refer back Figure 2A and Figure 2B, the mass flow controller 206 is a component capable of controlling the flow rate of the fluid 160 in the manifold 204. In some embodiments, the mass flow controller 206 includes an inlet port, an outlet port, a sensor (e.g., a mass flow sensor), and a raft (e.g., a proportional control valve). In some embodiments, the mass flow controller 206 receives an input signal from the controller 208, which indicates a value of mass flow. The mass flow controller 206 compares the indicated mass flow value with a value from the sensor of the mass flow controller 206 and adjusts the raft of the mass flow controller 206 to achieve the indicated flow rate. Although the radiation source 100 may include other mass flow controllers, the mass flow controller 206 can provide finer and more detailed flow control due to its ability to adjust or fine-tune the raft of the mass flow controller 206 based on feedback and / or input from the controller 208 to avoid flow imbalance when blockage or orifice blockage of the dynamic airlock nozzle 112 occurs. In some embodiments, the flow rate indicated by the controller 208 corresponds to the flow rate that the mass flow controller 206 will provide. In some embodiments, a mass flow controller 206 is mounted on each of the manifolds 204, such as Figure 2B In some embodiments, the mass flow controller 206 can communicate with the controller 208 (eg, via a wired connection or a wireless connection).

[0151] In some embodiments, the control system 200 includes a plurality of mass flow controllers 206. While other radiation sources may include a single mass flow controller to provide flow to the dynamic gas lock nozzles through a one-to-two manifold (which results in all dynamic gas lock nozzles sharing two sub-flows without fine control), the radiation source described herein includes a plurality of mass flow controllers 206, each of which is associated with a different dynamic gas lock nozzle control zone 210. For example, Figure 2B As shown, the control system 200 may include four mass flow controllers 206 - a mass flow controller 206a associated with the dynamic air-lock nozzle control zone 210a, a mass flow controller 206b associated with the dynamic air-lock nozzle control zone 210b, a mass flow controller 206c associated with the dynamic air-lock nozzle control zone 210c, and a mass flow controller 206d associated with the dynamic air-lock nozzle control zone 210d.

[0152] The controller 208 is a component (e.g., one or more processors) capable of controlling the flow rate in the dynamic airlock nozzle control zone 210 of the control system 200. For example, in some embodiments, the controller 208 can cause the one or more mass flow controllers 206 to adjust the flow rate in the one or more dynamic airlock nozzle control zones 210 based on the pressure detected by the pressure sensor 202. In some embodiments, the controller 208 can communicate with the pressure sensor 202 (e.g., receive a signal indicating the pressure detected by the pressure sensor 202) and communicate with the mass flow controller 206 (e.g., send a signal related to adjusting the flow rate). The following is about FIG. 3A to FIG. 3C Details regarding the operation of controller 208 related to controlling the flow rate in dynamic airlock nozzle control zone 210 are described.

[0153] As shown above, FIG. 2A to FIG. 2D Provided as an example. Other examples may differ from those regarding FIG. 2A to FIG. 2D described. FIG. 2A to FIG. 2D The number and arrangement of components shown in the figure are provided as an example. FIG. 2A to FIG. 2D As with the components shown, there may be additional components, fewer components, different components, or a different arrangement of components.

[0154] FIG. 3A to FIG. 3C 1 is a diagram illustrating an embodiment of operations performed by control system 200 in connection with reducing or preventing particulate deposition as described herein. Figure 3A is a general example of operations performed by the control system 200 in connection with controlling the flow rate in the dynamic airlock nozzle control zone 210, and Figure 3B and Figure 3C Specific examples related to removing, mitigating, reducing, or preventing clogging of the dynamic airlock nozzle 110 of the intermediate focus cover 106 are illustrated.

[0155] like Figure 3A As shown in reference numeral 302 in the example 300, the controller 208 receives a plurality of signals. Here, each of the signals indicates a respective pressure detected by a corresponding pressure sensor 202 of the plurality of pressure sensors 202. In some embodiments, a given pressure sensor 202 provides signals periodically (automatically) (e.g., when the pressure sensor 202 is configured to provide signals during a specific period). In some embodiments, a given pressure sensor 202 provides signals upon request from the controller 208 (e.g., when the controller 208 sends a request to the pressure sensor 202 to perform a pressure measurement). In some embodiments, the controller 208 receives the plurality of signals after a period of time (e.g., when the pressure sensor 202 is configured to provide signals in a continuous manner such that the controller 208 receives the signals once during a specific time window).

[0156] In some embodiments, the controller 208 determines whether one or more dynamic airlock nozzles 110 of the intermediate focus cover 106 are at least partially blocked based on the pressure indicated by the signals from the plurality of pressure sensors 202 .

[0157] The flow continuity rule states that ρA1V1=ρA2V2, where A1 and A2 represent the cross-sectional areas at the outlet of a given pair of dynamic airlock nozzles 110, V1 and V2 represent the flow velocities at the outlet of this pair of dynamic airlock nozzles 110, and ρ is the mass density of the fluid 160. The flow continuity rule indicates that if one of the dynamic airlock nozzles 110 is at least partially blocked (e.g., particle deposition), the flow velocity at the outlet of this dynamic airlock nozzle 110 increases compared to the flow velocity at the unblocked dynamic airlock nozzle 110 (e.g., if A1 decreases compared to A2, then V1 increases compared to V2). When the flow velocity changes, White-Neuve's law can be applied to the flow field to determine the pressure change: P1+1 / 2ρV1 2 +gh1=P2+1 / 2ρV2 2 +gh2, where P1 and P2 represent the pressure at the outlet of the pair of dynamic airlock nozzles 110, g is the gravitational acceleration, and h1 and h2 represent the height at the outlet of the pair of dynamic airlock nozzles 110. Therefore, if the flow rate at the outlet of one of the dynamic airlock nozzles 110 increases compared to the flow rate at the outlet of the other dynamic airlock nozzle 110, the pressure at the outlet of that dynamic airlock nozzle 110 decreases compared to the pressure at the outlet of the other dynamic airlock nozzle 110 (for example, if V1 increases compared to V2, P1 decreases compared to P2). Here, because the manifolds 204 supplying the fluid 160 share the same gas source, the manifolds 204 share the same total pressure, which means that it is possible to determine whether a specific dynamic airlock nozzle 110 is partially blocked based on comparing the pressure detected at the outlet of the dynamic airlock nozzle 110 with the pressure at the outlet of the other dynamic airlock nozzle 110.

[0158] Therefore, in some embodiments, the controller 208 determines whether the dynamic airlock nozzle 110 is at least partially blocked based on the pressure detected by the pressure sensor 202 associated with the dynamic airlock nozzle 110 (e.g., the dynamic airlock nozzle 110 on which the pressure sensor 202 is installed). For example, the controller 208 may receive a first signal from a first pressure sensor 202, the first pressure sensor 202 being associated with a first dynamic airlock nozzle 110 included in a first dynamic airlock nozzle control zone 210, wherein the first signal indicates the pressure measured at the first dynamic airlock nozzle 110 at a specific time. Similarly, the controller 208 may receive a second signal from a second pressure sensor 202, the second pressure sensor 202 being associated with a second dynamic airlock nozzle 110 included in a second dynamic airlock nozzle control zone 210, wherein the second signal indicates the pressure measured at the second dynamic airlock nozzle 110 at a specific time. The controller 208 may then determine whether the difference between the pressure indicated by the first signal and the pressure indicated by the second signal exceeds a critical value (e.g., 10% or more). Here, if the controller 208 determines that the difference between the pressure indicated by the first signal and the pressure indicated by the second signal exceeds a critical value (for example, the pressure at the first dynamic airlock nozzle 110 is at least 10% less than the pressure at the second dynamic airlock nozzle 110), the controller 208 may determine that the first dynamic airlock nozzle 110 is at least partially blocked. On the contrary, if the controller 208 determines that the difference between the pressure indicated by the first signal and the pressure indicated by the second signal does not exceed a critical value (for example, the difference between the pressure at the first dynamic airlock nozzle 110 and the pressure at the second dynamic airlock nozzle 110 is less than 10%), the controller 208 may determine that the first dynamic airlock nozzle 110 and the second dynamic airlock nozzle 110 are not blocked. In some embodiments, in order to confirm the judgment of whether the first dynamic airlock nozzle 110 or the second dynamic airlock nozzle 110 is at least partially blocked or unblocked, the controller 208 may perform one or more additional comparisons of the pressure at the first dynamic airlock nozzle 110 and / or the pressure at the second dynamic airlock nozzle 110 with the pressure at one or more other dynamic airlock nozzles 110 (for example, the third dynamic airlock nozzle 110, the fourth dynamic airlock nozzle 110, etc.).

[0159] It should be noted that in the above example, to determine whether the first dynamic airlock nozzle 110 or the second dynamic airlock nozzle 110 is blocked, the controller 208 compares the pressure at the first dynamic airlock nozzle 110 with the pressure at the second dynamic airlock nozzle 110. However, in some embodiments, the controller 208 may be configured to determine whether a given dynamic airlock nozzle 110 is blocked in another manner, such as by comparing the pressure at the specific dynamic airlock nozzle 110 with a reference pressure (e.g., a pressure expected by the control system 200, a pressure measured at a known unblocked dynamic airlock nozzle 110, an average pressure calculated from a subset of all or a specific dynamic airlock nozzle 110, a pressure measured at an earlier specific dynamic airlock nozzle 110, or the like). In some embodiments, the controller 208 makes a similar determination for each dynamic airlock nozzle 110 of the intermediate focus cover 106 (e.g., in a specific order, in a random order, in a group at the same time, or the like).

[0160] like Figure 3A As further shown by reference number 304 in the example 300, the controller 208 determines based on the plurality of signals that a particular dynamic airlock nozzle 110 of the intermediate focus cover 106 is at least partially blocked.

[0161] As indicated by reference numeral 306 , the controller 208 causes one or more mass flow controllers 206 to adjust flow rates in one or more dynamic airlock nozzle control zones 210 based on a determination that a particular dynamic airlock nozzle 110 is at least partially blocked.

[0162] In some embodiments, the controller 208 increases the flow rate in the dynamic airlock nozzle control zone 210 that includes a particular dynamic airlock nozzle 110 that is at least partially blocked. Figure 3B is a schematic diagram illustrating an example timeline of events that may occur, wherein the controller 208 increases the flow rate in the dynamic airlock nozzle control zone 210 including a particular dynamic airlock nozzle 110 that is at least partially blocked. Figure 3BAs shown, the controller 208 may provide a signal indicating the mass flow rate at which the flow rate will be increased to the mass flow controller 206 that controls the flow rate of the dynamic airlock nozzle control zone 210. Here, the mass flow controller 206 receives the signal from the controller 208 and adjusts the mass flow rate accordingly (e.g., by increasing the opening rate of the mass flow controller 206, thereby increasing the flow rate in the dynamic airlock nozzle control zone 210). In some embodiments, in order to try to blow away the blockage of the dynamic airlock nozzle 110, the controller 208 increases the flow rate of the dynamic airlock nozzle control zone 210. In some embodiments, during the attempt to blow away the blockage of the dynamic airlock nozzle 110 (e.g., increasing the flow rate in the dynamic airlock nozzle control zone 210 with the blocked dynamic airlock nozzle 110), the controller 208 may reduce the flow rate in one or more other dynamic airlock nozzle control zones 210 (e.g., by reducing the opening rate of one or more other mass flow controllers 206). In this example, the controller 208 may receive (e.g., at a later time) a signal indicating another pressure detected by the pressure sensor 202 associated with a particular dynamic airlock nozzle 110 that was once partially blocked. Here, the controller 208 may determine whether the particular dynamic airlock nozzle 110 remains partially blocked based on the other pressure. If the particular dynamic airlock nozzle 110 is no longer blocked, the controller 208 may cause one or more mass flow controllers 206 to adjust the flow rate in the dynamic airlock nozzle control area 210 so that the flow rate returns to a specific level (e.g., so that the flow rate in the dynamic airlock nozzle control area 210 with the now unblocked dynamic airlock nozzle 110 returns to a normal operating level). In this way, the controller 208 may attempt to reduce or remove the blockage detected by the control system 200.

[0163] In some embodiments, the controller 208 reduces the flow rate in the dynamic airlock nozzle control zone 210 that includes a particular dynamic airlock nozzle 110 that is at least partially blocked. Figure 3C is a schematic diagram illustrating an example timeline of events that may occur, wherein the controller 208 causes a flow rate in the dynamic airlock nozzle control area 210 including a particular dynamic airlock nozzle 110 that is at least partially blocked to be reduced. Figure 3CAs shown, the controller 208 may provide a signal indicating the mass flow rate at which the flow rate will be reduced to the mass flow controller 206 that controls the flow rate of the dynamic airlock nozzle control zone 210. Here, the mass flow controller 206 receives the signal from the controller 208 and adjusts the mass flow rate accordingly (for example, by reducing the opening rate of the mass flow controller 206, thereby reducing the flow rate in the dynamic airlock nozzle control zone 210). In some embodiments, in order to prevent the asymmetric particle deposition from worsening, the controller 208 reduces the flow rate of the dynamic airlock nozzle control zone 210 of a specific dynamic airlock nozzle 110 that has at least partial obstruction. Here, the controller 208 may reduce the flow rate so that the pressure at the dynamic airlock nozzle 110 matches the pressure at the unobstructed dynamic airlock nozzle 110 in another dynamic airlock nozzle control zone 210. It should be noted that in this example, the controller 208 does not remove the obstruction. Instead, the controller 208 attempts to mitigate the effects of the obstruction to prevent the asymmetric deposition from further worsening. In some embodiments, the controller 208 may implement this mitigation technique after unsuccessfully attempting to blow away the obstruction in the manner described in the above examples. That is, in some embodiments, after the controller 208 increases the flow rate in the dynamic airlock nozzle control zone 210, the controller 208 decreases the flow rate in the dynamic airlock nozzle control zone 210 containing the particular dynamic airlock nozzle 110 that is at least partially obstructed.

[0164] In this way, the controller 208 can selectively enable one or more mass flow controllers 206 to adjust the flow rate in one or more dynamic airlock nozzle control zones 210 according to the pressure detected by the pressure sensor 202 in the dynamic airlock nozzle control zone 210 .

[0165] As shown above, FIG. 3A to FIG. 3C Provided as an example. Other examples may differ from those regarding FIG. 3A to FIG. 3C described.

[0166] It should be noted that the first group of pressure sensors 202 included in the dynamic airlock nozzle control area 210 and the second group of pressure sensors 202 included in the dynamic airlock nozzle control area 210 are located at different distances from the outlet of the manifold 204. Therefore, the pressure detected by the pressure sensors 202 in the first group may be slightly different from the pressure detected by the pressure sensors 202 in the second group, even if there is no blockage of the dynamic airlock nozzle 110. In such a case, when comparing the detected pressures, these groups of pressure sensors 202 (for example, with respect to the above Figure 3A description method).

[0167] Figure 4 FIG. 2 is a schematic diagram showing an implementation of dividing the pressure sensor 202 of the control system 200 into a plurality of sensor groups. Figure 4In the embodiment of the present invention, each pressure sensor 202 in a first group of pressure sensors 202 (labeled as pressure sensor 202 group 1) is located at substantially the same distance from a given manifold 204 (e.g., the pressure sensors 202 in the first group are the pressure sensors 202 closest to the outlet of the manifold 204). Similarly, each pressure sensor 202 in a second group of pressure sensors 202 (labeled as pressure sensor 202 group 2) is located at substantially the same distance from a given manifold 204 (e.g., the pressure sensors 202 in the second group are the pressure sensors 202 farthest from the outlet of the manifold 204). Here, the control system 200 can be configured so that the pressure detected by one pressure sensor 202 in a particular group is only compared with the pressure detected by the pressure sensors 202 in the particular group. For example, the pressure indicated by one pressure sensor 202 in the first group may be compared only to the pressures indicated by other pressure sensors 202 in the first group that are relevant to detecting blockages, and the pressure indicated by one pressure sensor 202 in the second group may be compared only to the pressures indicated by other pressure sensors 202 in the second group that are relevant to detecting blockages. In this way, the accuracy or reliability of detecting blockage of a given dynamic airlock nozzle 110 may be increased.

[0168] As shown above, Figure 4 Provided as an example. Other examples may differ from Figure 4 described.

[0169] In the above example, the intermediate focus cover 106 includes 16 dynamic air lock nozzles 110, 16 dynamic air lock nozzles 112, and 4 fluid channels 116. In addition, the control system 200 includes 16 pressure sensors 202 (one for each dynamic air lock nozzle 110), 4 manifolds 204 (one for each fluid channel 116), and 4 dynamic air lock nozzle control zones 210 (each including 4 dynamic air lock nozzles 110). These numbers are provided for illustrative purposes. In practice, other numbers of one, more, or all of these components may be used with the intermediate focus cover 106 and / or the control system 200.

[0170] FIG. 5A to FIG. 5E is a schematic diagram illustrating additional embodiments of the intermediate focus cover 106 and the control system 200 described herein.

[0171] exist Figure 5AIn the example shown, the intermediate focus cover 106 includes 16 dynamic air lock nozzles 110, 16 dynamic air lock nozzles 112, and 4 fluid channels 116. In addition, the control system 200 includes 8 pressure sensors 202a1, 202a2, 202b1, 202b2, 202c1, 202c2, 202d1, and 202d2 (one for every two dynamic air lock nozzles 110); 4 manifolds 204a to 204d (one for each fluid channel 116); and 4 dynamic air lock nozzle control areas 210a, 210b, 210c, and 210d (each including 4 dynamic air lock nozzles 110). In this embodiment, blockage is monitored at half of the dynamic air lock nozzles 110. In such a case, it can be assumed that the state (e.g., unblocked or at least partially blocked) of a given dynamic airlock nozzle 110 without a pressure sensor 202 is similar to the state of an adjacent dynamic airlock nozzle 110 with a pressure sensor 202. Figure 5A The illustrated embodiment (eg, an embodiment having a fewer number of pressure sensors 202 than the dynamic airlock nozzle 110 ) reduces the complexity and cost of the control system 200 , thereby increasing manufacturability.

[0172] exist Figure 5B In the example shown, the intermediate focus cover 106 includes 16 dynamic airlock nozzles 110, 16 dynamic airlock nozzles 112, and 2 fluid channels 116. In addition, the control system 200 includes 16 pressure sensors 202a1 to 202a8 and pressure sensors 202b1 to 202b8 (one for each dynamic airlock nozzle 110), 2 manifolds 204 (one for each fluid channel 116), and 2 dynamic airlock nozzle control areas 210 (each including 8 dynamic airlock nozzles 110). In this embodiment, each half of the group of dynamic airlock nozzles 110 controls the flow rate independently. Figure 5B The embodiment shown (for example, having a ratio Figure 2B The relatively small number of fluid channels 116, manifold 204, and dynamic airlock nozzle control area 210 shown in the embodiment of the present invention reduces the complexity and cost of the control system 200, thereby increasing manufacturability.

[0173] exist Figure 5CIn the example shown, the intermediate focus cover 106 includes 16 dynamic airlock nozzles 110, 16 dynamic airlock nozzles 112, and 2 fluid channels 116. In addition, the control system 200 includes 8 pressure sensors 202 (one for every two dynamic airlock nozzles 110), 2 manifolds 204 (one for each fluid channel 116), and 2 dynamic airlock nozzle control areas 210 (each including 8 dynamic airlock nozzles 110). In this embodiment, blockage is monitored at half of the dynamic airlock nozzles 110. In such a case, it can be assumed that the state of a given dynamic airlock nozzle 110 without the pressure sensor 202 (e.g., unblocked or at least partially blocked) is similar to the state of an adjacent dynamic airlock nozzle 110 with the pressure sensor 202. In addition, the flow rate of each half of the group of dynamic airlock nozzles 110 is independently controlled. As Figure 5C The embodiment shown (e.g., having a smaller number of pressure sensors 202 than the dynamic air lock nozzle 110 and having a smaller number of pressure sensors 202 than the dynamic air lock nozzle 110) Figure 2B The relatively small number of fluid channels 116, manifold 204, and dynamic airlock nozzle control area 210 shown in the embodiment of the present invention reduces the complexity and cost of the control system 200, thereby increasing manufacturability.

[0174] exist Figure 5D In the example shown, the intermediate focus cover 106 includes 16 dynamic air lock nozzles 110, 16 dynamic air lock nozzles 112, and 8 fluid channels 116. In addition, the control system 200 includes 16 pressure sensors 202 (one for each dynamic air lock nozzle 110), 8 manifolds 204a to 204h (one for each fluid channel 116), 8 mass flow controllers 206a to 206h, and 8 dynamic air lock nozzle control zones 210a to 210h (each including 2 dynamic air lock nozzles 110). It should be noted that for the purpose of clarity, the pressure sensors 202 are not labeled. Figure 5D In this embodiment, each pair of dynamic air lock nozzles 110 in a group of dynamic air lock nozzles 110 independently controls the flow rate. Figure 5D The embodiment shown (for example, having a ratio Figure 2B The relatively large number of manifolds 204 and the dynamic airlock nozzle control area 210 shown in the embodiment increase the accuracy of flow field control, which means that the effectiveness of the dynamic airlock can be improved.

[0175] exist Figure 5EIn the example shown, the intermediate focus cover 106 includes 16 dynamic air lock nozzles 110, 16 dynamic air lock nozzles 112, and 8 fluid channels 116. In addition, the control system 200 includes 8 pressure sensors 202 (one for every two dynamic air lock nozzles 110), 8 manifolds 204a to 204h (one for each fluid channel 116), 8 mass flow controllers 206a to 206h, and 8 dynamic air lock nozzle control zones 210a to 210h (each including 2 dynamic air lock nozzles 110). It should be noted that for the purpose of clarity, the pressure sensors 202 are not labeled. Figure 5E In this embodiment, each pair of dynamic air lock nozzles 110 in a group of dynamic air lock nozzles 110 independently controls the flow rate. Figure 5E The embodiment shown (e.g., having a smaller number of pressure sensors 202 than the dynamic air lock nozzle 110 and having a smaller number of pressure sensors 202 than the dynamic air lock nozzle 110) Figure 2B The relatively larger number of manifolds 204 and dynamic airlock nozzle control areas 210 shown in the embodiment of FIG. 1 increase the accuracy of flow field control, which means that the performance of the dynamic airlock can be improved while mitigating cost increases (for example, by using fewer pressure sensors 202).

[0176] As shown above, FIG. 5A to FIG. 5E Provided as an example. Other examples may differ from those regarding FIG. 5A to FIG. 5E described. FIG. 5A to FIG. 5E The number and arrangement of components shown are provided as an example. FIG. 5A to FIG. 5E As with the components shown, there may be additional components, fewer components, different components, or a different arrangement of components.

[0177] Figure 6 is a schematic diagram illustrating an embodiment of components of one or more devices of the control system 200 . Figure 6 6 is a schematic diagram of exemplary components of device 600, which may correspond to one or more pressure sensors 202, one or more mass flow controllers 206, and / or controller 208. In some embodiments, one or more pressure sensors 202, one or more mass flow controllers 206, and / or controller 208 may include one or more devices 600 and / or one or more components of device 600. Figure 6 As shown, the device 600 may include a bus 610 , a processor 620 , a memory 630 , a storage component 640 , an input component 650 , an output component 660 , and a communication component 670 .

[0178] Bus 610 includes components that enable wired and / or wireless communication between components of device 600. Processor 620 includes a central processing unit, a graphics processing unit, a microprocessor, a controller, a microcontroller, a digital signal processor, a field encodeable gate array, a special application integrated circuit, and / or another type of processing component. Processor 620 is implemented in hardware, firmware, or a combination of hardware and firmware. In some embodiments, processor 620 includes one or more processors that can be encoded to perform functions. Memory 630 includes random access memory, read-only memory, and / or another type of memory (e.g., flash memory, magnetic memory, and / or optical memory).

[0179] Storage component 640 stores information and / or software related to the operation of device 600. For example, storage component 640 may include a hard disk, a magnetic disk, an optical drive, a solid state drive, an optical disk, a digital versatile disk, and / or another type of non-transitory computer readable medium. Input component 650 enables device 600 to receive input, such as user input and / or sensory input. For example, input component 650 may include a touch screen, a keyboard, a keypad, a mouse, a button, a microphone, a switch, a sensor, a global positioning system component, an accelerometer, a gyroscope, and / or an actuator. Output component 660 enables device 600 to provide output, such as through a display, a speaker, and / or one or more light emitting diodes. Communication component 670 enables device 600 to communicate with other devices, such as through a wired connection and / or a wireless connection. For example, communication component 670 may include a receiver, a transmitter, a transceiver, a modem, a network interface card, and / or an antenna.

[0180] The device 600 may perform one or more processes described herein. For example, a non-transitory computer storage medium (e.g., memory 630 and / or storage component 640) may store a set of instructions (e.g., one or more instructions, codes, software codes, and / or program codes) that are executed by the processor 620. The processor 620 may execute the set of instructions to perform one or more processes described herein. In some embodiments, the one or more processors 620 execute the set of instructions so that the one or more processors 620 and / or the device 600 may perform one or more processes described herein. In some embodiments, hard-wired circuitry may be used in place of or in combination with the instructions to perform one or more processes described herein. Thus, the embodiments described herein are not limited to any particular combination of hardware circuitry and software.

[0181] Figure 6 The number and arrangement of components shown are provided as an example. Figure 6The components shown, device 600 may include additional components, fewer components, different components, or components in a different configuration. Additionally or alternatively, a set of components (e.g., one or more components) of device 600 may perform one or more functions described as performed by another set of components of device 600.

[0182] Figure 7 FIG. 7 is a flow chart illustrating an embodiment of a process 700 for improving flow rate control at a dynamic airlock nozzle of an intermediate focus cover. In some embodiments, a controller (eg, controller 208) may be used to perform Figure 7 In some embodiments, the control may be performed by another device or a set of devices separate from or including the controller, such as one or more pressure sensors (e.g., one or more pressure sensors 202) and / or one or more mass flow controllers (e.g., one or more mass flow controllers 206). Figure 7 Additionally or alternatively, one or more components of the device 600, such as the processor 620, the memory 630, the storage component 640, the input component 650, the output component 660, and / or the communication component 670, may be performed. Figure 7 One or more process blocks.

[0183] like Figure 7 As shown, process 700 may include receiving a plurality of signals from a plurality of pressure sensors (block 710). For example, controller 208 may receive a plurality of signals from a plurality of pressure sensors 202, as described above. In some embodiments, each of the plurality of signals indicates a respective pressure detected by a corresponding pressure sensor 202 in the plurality of pressure sensors 202.

[0184] like Figure 7 As further shown, the process 700 may include determining that one of the plurality of dynamic airlock nozzles of the intermediate focus cover is at least partially blocked based on the plurality of signals (block 720). For example, the controller 280 may determine that one of the plurality of dynamic airlock nozzles of the intermediate focus cover 106 is at least partially blocked based on the plurality of signals, as described above.

[0185] like Figure 7As further shown, the process 700 may include causing one or more of the plurality of mass flow controllers to adjust a flow rate in one or more of the plurality of dynamic airlock nozzle control zones based on determining that the dynamic airlock nozzle is at least partially blocked (block 730). For example, the controller 208 may cause one or more of the plurality of mass flow controllers 206 to adjust a flow rate in one or more of the plurality of dynamic airlock nozzle control zones 210 based on determining that the dynamic airlock nozzle 110 is at least partially blocked. In some embodiments, the at least partially blocked dynamic airlock nozzle 110 is included in one of the plurality of dynamic airlock nozzle control zones 210. In some embodiments, each of the plurality of mass flow controllers 260 is associated with a corresponding dynamic airlock nozzle control zone 210 in the plurality of dynamic airlock nozzle control zones 210.

[0186] The process 700 may include additional embodiments, such as any single embodiment or any combination of the embodiments described below and / or in connection with one or more other processes described elsewhere herein.

[0187] In a first embodiment, the controller 208 is configured to increase the flow rate in a dynamic airlock nozzle control zone 210 including an at least partially blocked dynamic airlock nozzle 110 by causing one or more mass flow controllers 206 to adjust the flow rate in one or more dynamic airlock nozzle control zones 210 .

[0188] In the second embodiment, whether alone or in combination with the first embodiment, the process 700 includes determining that a dynamic airlock nozzle 110 that was once at least partially blocked is no longer blocked, and causing one or more mass flow controllers 206 to adjust the flow rate in one or more dynamic airlock nozzle control areas 210 so that the flow rate in the dynamic airlock nozzle control area 210 including the dynamic airlock nozzle 110 that is no longer blocked is at a specific level.

[0189] In a third embodiment, either alone or in combination with one or more of the first and second embodiments, the controller 208 is configured to reduce the flow rate in a dynamic airlock nozzle control zone 210 including a dynamic airlock nozzle 110 that is at least partially blocked by causing one or more mass flow controllers to adjust the flow rate in one or more dynamic airlock nozzle control zones 210.

[0190] In a fourth embodiment, whether alone or in combination with the third embodiment, after causing one or more mass flow controllers 206 to increase the flow rate in a dynamic airlock nozzle control area 210 including a dynamic airlock nozzle 110 that is at least partially blocked, the controller 208 is configured to reduce the flow rate in the dynamic airlock nozzle control area 210 including a dynamic airlock nozzle 110 that is at least partially blocked.

[0191] Although Figure 7 An example block diagram of process 700 is shown. In some embodiments, compared to Figure 7 As depicted, process 700 may include additional blocks, fewer blocks, different blocks, or blocks in a different configuration. Additionally or alternatively, two or more of processes 700 may be performed in parallel.

[0192] Figure 8 is a schematic diagram illustrating an embodiment of a lithography system 800 described herein. The lithography system 800 comprises an extreme ultraviolet lithography system or another type of lithography system configured to transfer a pattern to a semiconductor substrate using mirror-based optics. The lithography system 800 can be configured for use in a semiconductor processing environment, such as a semiconductor fabrication plant or semiconductor manufacturing facility.

[0193] like Figure 8 As shown, lithography system 800 includes radiation source 100 and exposure tool 802. Radiation source 100 (e.g., an EUV radiation source or another type of radiation source) is configured to generate radiation 158, such as EUV radiation and / or another type of electromagnetic radiation (e.g., light). Exposure tool 802 (e.g., an EUV scanner or another type of exposure tool) is configured to focus radiation 158 onto a reflective reticle 804 (or mask) so that radiation 158 can be used to transfer a pattern from reticle 804 to semiconductor substrate 806.

[0194] The light collector 104 or radiation source includes a curved mirror configured to collect radiation 158 generated by the radiation source 100 and focus the radiation 158 toward an intermediate focus 808. The radiation 158 is generated from a plasma (e.g., plasma 154) generated by exposing a target material 152 (e.g., tin (Sn) droplets or another type of droplets) to a laser beam 150. A droplet generator (DG) head 810 provides the target material 152 across the front face of the light collector 104. The droplet generator head 810 is pressurized to provide a precise and controlled output of the target material 152. The laser beam 150 is provided through an opening to generate a plasma at the front face of the light collector 104. The laser beam 150 is pulsed at a time point synchronized with the flow of the source material 152 from the droplet generator head 810.

[0195] The exposure tool 802 includes an emitter 812 and a projection optics box (POB) 814. The projection optics box 814 includes a plurality of mirrors configured to project radiation 158 onto a semiconductor substrate 806 after modifying the radiation 158 according to a pattern of the reticle 804. The exposure tool 802 includes a substrate stage 816 (e.g., a wafer stage) configured to support the semiconductor substrate 806. Additionally, the substrate stage 816 is configured to move (or step) the semiconductor substrate 806 through a plurality of exposure fields as the radiation 158 transfers a pattern from the reticle 804 to the semiconductor substrate 806.

[0196] In some embodiments, the exposure tool 802 includes a reticle stage (not shown) configured to support and / or secure the reticle 804. Additionally, the reticle stage is configured to move or slide the reticle through the radiation 158 such that the reticle 804 is scanned by the radiation 158. In this manner, a pattern that is larger than the field or beam of radiation 158 can be transferred to the semiconductor substrate 806.

[0197] The light emitter 812 includes a plurality of mirrors configured to focus and / or direct radiation 158 onto the doubling mask 804 to illuminate a pattern on the doubling mask 804. The light emitter 812 includes a mirror 818a and a mirror 818b. The mirror 818a includes a field facet mirror (FFM) or another type of mirror including a plurality of field facets. The mirror 818b includes a pupil facet mirror (PFM) or another type of mirror also including a plurality of pupil facets. The facets of the mirrors 818a and 818b are configured to focus, polarize, and / or otherwise adjust the radiation 158 from the radiation source 100 to increase the uniformity of the radiation 158 and / or to increase a particular type of radiation component (e.g., transverse electric (TE) polarized radiation or transverse magnetic (TM) polarized radiation).

[0198] Another mirror (e.g., a relay mirror) is included to direct radiation 158 from the illuminator 812 onto the doubling mask 804. The projection optics box 814 includes a plurality of mirrors, such as mirrors 822a to 822f. In some embodiments, the mirrors 822a to 822f are configured to focus or reduce the radiation 158 to an exposure field, which may include one or more die regions on the semiconductor substrate 806.

[0199] In an exemplary exposure operation (e.g., an EUV exposure operation), a droplet generator head 810 provides a stream of target material 152 across the front face of a condenser 104. A laser beam 150 contacts the source material 152, which creates a plasma 154. The plasma 154 emits or generates radiation 158 (e.g., EUV light). The radiation 158 is focused by the condenser 104 and enters the exposure machine 802 via a mirror 818a that directs the radiation source 100 toward the illuminator 812. The mirror 818a reflects the radiation 158 onto a mirror 818b, which reflects the radiation 158 toward the reticle 804 and onto a mirror 820. The radiation 158 is modified by a pattern in the reticle 804. In other words, the radiation 158 is reflected from the reticle 804 based on the pattern of the reticle 804. The reflective reticle 804 directs radiation 158 to a mirror 822a in the projection optics box 814, which reflects the radiation 158 onto a mirror 822b. The radiation 158 continues to be reflected and reduced in the projection optics box 814 by mirrors 822c through 822f. The mirror 822f reflects the radiation 158 onto the semiconductor substrate 806, thereby transferring the pattern of the reticle 804 to the semiconductor substrate 806. The above exposure operation is an example, and the lithography system 800 can be operated according to other EUV techniques and radiation paths including a greater number of mirrors, a fewer number of mirrors, and / or mirrors in a different configuration.

[0200] As shown above, Figure 8 Provided as an example. Other examples may differ from the Figure 8 described.

[0201] In this manner, the control system can reduce or prevent asymmetric particle (e.g., tin) deposition on the tapered wall of the dynamic airlock of the intermediate focus cover by controlling the flow rate at the dynamic airlock nozzle that can improve the dynamic airlock. Thus, the control system described herein reduces the likelihood of delivering particles toward the reticle to the scanner, thereby reducing the likelihood of forming defects, which means improving pattern quality and wafer yield, and preventing damage to the scanner.

[0202] As described in more detail above, some embodiments described herein provide an extreme ultraviolet source. This extreme ultraviolet source includes a plurality of dynamic airlock nozzles. This extreme ultraviolet source includes a plurality of pressure sensors, wherein each of the plurality of pressure sensors detects the pressure in a corresponding dynamic airlock nozzle control zone in a plurality of dynamic airlock nozzle control zones, wherein each dynamic airlock nozzle control zone includes a different set of dynamic airlock nozzles from a plurality of dynamic airlock nozzles, wherein each of the plurality of pressure sensors is configured at a different dynamic airlock nozzle in a plurality of dynamic airlock nozzles. This extreme ultraviolet source includes a plurality of mass flow controllers (MFCs), wherein each of the plurality of mass flow controllers controls the flow rate in a corresponding dynamic airlock nozzle control zone in a plurality of dynamic airlock nozzle control zones, wherein each of the plurality of mass flow controllers is associated with a different dynamic airlock nozzle control zone in a plurality of dynamic airlock nozzle control zones. This extreme ultraviolet source includes a plurality of manifolds, wherein each manifold connects a different dynamic airlock nozzle control zone in a plurality of dynamic airlock nozzle control zones.

[0203] According to some embodiments, a plurality of pressure sensors are mounted at a first row of dynamic airlock nozzles of an intermediate focus (IF) cover of an extreme ultraviolet source. According to some embodiments, a corresponding pressure sensor of the plurality of pressure sensors is mounted at each dynamic airlock nozzle of a particular row of dynamic airlock nozzles of the intermediate focus (IF) cover. According to some embodiments, each dynamic airlock nozzle control zone of the plurality of dynamic airlock nozzle control zones comprises the same number of dynamic airlock nozzles. According to some embodiments, the plurality of dynamic airlock nozzle control zones comprises at least four dynamic airlock nozzle control zones. According to some embodiments, the plurality of manifolds comprises at least four manifolds. According to some embodiments, in the plurality of manifolds, a distance of a fluid path passing through each of the plurality of manifolds is substantially the same.

[0204] As described in more detail above, some embodiments described herein provide a method for improving asymmetric deposition. The method includes receiving a plurality of signals from a plurality of pressure sensors by a controller associated with a radiation source, each of the plurality of signals indicating a corresponding pressure detected by a corresponding pressure sensor in the plurality of pressure sensors. The method includes determining, by the controller and based on the plurality of signals, that one of a plurality of dynamic airlock nozzles of an intermediate focus cover is at least partially blocked. The method includes, based on determining that the dynamic airlock nozzle is at least partially blocked, causing one or more of a plurality of mass flow controllers to adjust a flow rate in one or more of a plurality of dynamic airlock nozzle control zones by the controller, wherein the at least partially blocked dynamic airlock nozzle is included in one of the plurality of dynamic airlock nozzle control zones, wherein each of the plurality of mass flow controllers is associated with a corresponding dynamic airlock nozzle control zone in the plurality of dynamic airlock nozzle control zones.

[0205] According to some embodiments, increasing the flow rate in a dynamic airlock nozzle control zone including a dynamic airlock nozzle that is at least partially blocked includes causing one or more mass flow controllers to adjust the flow rate in one or more dynamic airlock nozzle control zones. According to some embodiments, the method further includes determining that a dynamic airlock nozzle that was once at least partially blocked is no longer blocked, and causing one or more mass flow controllers to adjust the flow rate in one or more dynamic airlock nozzle control zones so that the flow rate in the dynamic airlock nozzle control zone including the dynamic airlock nozzle that is no longer blocked is a specific standard. According to some embodiments, reducing the flow rate in a dynamic airlock nozzle control zone including a dynamic airlock nozzle that is at least partially blocked includes causing one or more mass flow controllers to adjust the flow rate in one or more dynamic airlock nozzle control zones. According to some embodiments, after causing one or more mass flow controllers to increase the flow rate in the dynamic airlock nozzle control zone including the dynamic airlock nozzle that is at least partially blocked, the flow rate in the dynamic airlock nozzle control zone including the dynamic airlock nozzle that is at least partially blocked is reduced.

[0206] As described in more detail above, some embodiments described herein provide a radiation source. The radiation source includes a plurality of pressure sensors, wherein each of the plurality of pressure sensors is disposed at a corresponding dynamic airlock nozzle of a plurality of dynamic airlock nozzles of an intermediate focus cover, wherein each of the plurality of pressure sensors provides a signal indicating a corresponding pressure at a corresponding dynamic airlock nozzle of the plurality of dynamic airlock nozzles. The radiation source includes a plurality of mass flow controllers, wherein each of the plurality of mass flow controllers controls a flow rate in a corresponding dynamic airlock nozzle control zone of a plurality of dynamic airlock nozzle control zones, wherein each dynamic airlock nozzle control zone is associated with a corresponding subset of dynamic airlock nozzles from the plurality of dynamic airlock nozzles. The radiation source includes a plurality of manifolds, wherein each of the plurality of manifolds provides fluid to a corresponding dynamic airlock nozzle control zone of the plurality of dynamic airlock nozzle control zones.

[0207] According to some embodiments, the radiation source further includes a controller configured to control a plurality of mass flow controllers associated with adjusting flow rates in a plurality of dynamic airlock nozzle control zones based on pressures detected by a plurality of pressure sensors. According to some embodiments, a plurality of dynamic airlock nozzles provided with a plurality of pressure sensors are located in a first row of dynamic airlock nozzles of an intermediate focus cover. According to some embodiments, a corresponding pressure sensor of a plurality of pressure sensors is provided at each dynamic airlock nozzle of a particular row of dynamic airlock nozzles of an intermediate focus cover. According to some embodiments, each subset of dynamic airlock nozzles includes at least four dynamic airlock nozzles of a first row of dynamic airlock nozzles of an intermediate focus cover. According to some embodiments, a plurality of dynamic airlock nozzle control zones include two or more dynamic airlock nozzle control zones. According to some embodiments, a plurality of manifolds include two or more manifolds. According to some embodiments, in a plurality of manifolds, a distance of a fluid path passing through each of a plurality of manifolds is substantially the same.

[0208] The above disclosure summarizes the features of several embodiments so that those skilled in the art can better understand the aspects of the present disclosure. Those skilled in the art should understand that they can easily use the present disclosure as a basis to design or modify other processes and structures to achieve the same purpose and / or achieve the same advantages as the embodiments introduced herein. Those skilled in the art should also understand that such equal architecture does not depart from the spirit and scope of the present disclosure, and they can make various changes, substitutions, and modifications here without departing from the spirit and scope of the present disclosure.

Claims

1. An extreme ultraviolet source, characterized in that: The EUV source contains: Multiple dynamic air lock nozzles; a plurality of pressure sensors, wherein each of the pressure sensors detects a pressure in a corresponding one of the plurality of dynamic airlock nozzle control zones, wherein each of the dynamic air lock nozzle control zones comprises a different set of dynamic air lock nozzles from the dynamic air lock nozzles, and Each of the pressure sensors is disposed at a different dynamic air lock nozzle of the dynamic air lock nozzles; a plurality of mass flow controllers, wherein each of the mass flow controllers controls a flow rate in a corresponding one of the dynamic airlock nozzle control zones, wherein each of the mass flow controllers is associated with a different one of the dynamic airlock nozzle control zones; as well as A plurality of manifolds, wherein each of the manifolds is connected to a different one of the dynamic airlock nozzle control zones.

2. The extreme ultraviolet source according to claim 1, characterized in that The pressure sensors are mounted at a first row of dynamic airlock nozzles of an intermediate focus cap of the EUV source.

3. The extreme ultraviolet source according to claim 1, characterized in that A corresponding one of the pressure sensors is mounted at each of the dynamic air lock nozzles in a first row of the dynamic air lock nozzles of an intermediate focus cover.

4. The extreme ultraviolet source according to claim 1, characterized in that Each of the dynamic air-lock nozzle control zones includes the same number of the dynamic air-lock nozzles.

5. The extreme ultraviolet source according to claim 1, characterized in that The dynamic air-lock nozzle control zones include at least four dynamic air-lock nozzle control zones.

6. The extreme ultraviolet source according to claim 1, characterized in that The manifolds include at least four manifolds.

7. The extreme ultraviolet source according to claim 1, characterized in that In the manifolds, distances of the fluid paths passing through each of the manifolds are the same.

8. A method for improving asymmetric deposition, characterized in that: The method includes: receiving, by a controller associated with a radiation source, a plurality of signals from a plurality of pressure sensors, each of the signals indicating a respective pressure detected by a corresponding one of the pressure sensors; Determining, by the controller and based on the signals, that a dynamic air lock nozzle among a plurality of dynamic air lock nozzles of an intermediate focus cover is at least partially blocked; as well as By means of the controller, one or more mass flow controllers among the plurality of mass flow controllers adjust the flow rate in one or more dynamic air lock nozzle control areas among the plurality of dynamic air lock nozzle control areas according to determining that the dynamic air lock nozzle is at least partially blocked, wherein the at least partially blocked dynamic air lock nozzle is contained in a dynamic air lock nozzle control zone among the dynamic air lock nozzle control zones, and Each of the mass flow controllers is associated with a corresponding one of the dynamic air-lock nozzle control zones.

9. The method according to claim 8, characterized in that Causing the one or more mass flow controllers to adjust the flow rate in the one or more dynamic airlock nozzle control zones includes increasing the flow rate in the dynamic airlock nozzle control zone including the at least partially blocked dynamic airlock nozzle.

10. The method according to claim 9, characterized in that It also includes determining that the dynamic air-lock nozzle that was once at least partially blocked is no longer blocked, and causing the one or more mass flow controllers to adjust the flow rate in the one or more dynamic air-lock nozzle control areas so that the flow rate in the dynamic air-lock nozzle control area including the dynamic air-lock nozzle that is no longer blocked is at a level of the unblocked dynamic air-lock nozzle in normal operation.

11. The method according to claim 8, characterized in that Causing the one or more mass flow controllers to adjust the flow rate in the one or more dynamic airlock nozzle control zones includes reducing the flow rate in the dynamic airlock nozzle control zone including the at least partially blocked dynamic airlock nozzle.

12. The method according to claim 11, characterized in that After causing the one or more mass flow controllers to increase the flow rate in the dynamic airlock nozzle control area including the at least partially blocked dynamic airlock nozzle, the flow rate in the dynamic airlock nozzle control area including the at least partially blocked dynamic airlock nozzle is reduced.

13. A radiation source, characterized in that: The radiation source includes: a plurality of pressure sensors, wherein each of the pressure sensors is disposed at a corresponding one of a plurality of dynamic air lock nozzles of an intermediate focus cover, wherein each of the pressure sensors provides a signal indicative of a respective pressure at a corresponding one of the dynamic airlock nozzles; a plurality of mass flow controllers, wherein each of the mass flow controllers controls a flow rate in a corresponding one of the plurality of dynamic airlock nozzle control zones, wherein each of the dynamic airlock nozzle control zones is associated with a corresponding subset of dynamic airlock nozzles from the dynamic airlock nozzles; as well as A plurality of manifolds, wherein each of the manifolds provides a fluid to a corresponding one of the dynamic airlock nozzle control zones.

14. The radiation source according to claim 13, characterized in that The radiation source also includes a controller configured to control the mass flow controllers associated with adjusting the flow rates in the dynamic airlock nozzle control zones based on the pressures detected by the pressure sensors.

15. The radiation source of claim 13, wherein: The dynamic air lock nozzles on which the pressure sensors are mounted are located in a first row of the dynamic air lock nozzles of the intermediate focus cover.

16. The radiation source of claim 13, wherein: A corresponding one of the pressure sensors is positioned at each of the dynamic air lock nozzles in a first row of the intermediate focus cover.

17. The radiation source of claim 13, wherein: Each of the subsets of dynamic airlock nozzles includes at least four dynamic airlock nozzles of a first row of the dynamic airlock nozzles of the intermediate focus cover.

18. The radiation source of claim 13, wherein: The dynamic air-lock nozzle control zones include two or more dynamic air-lock nozzle control zones.

19. The radiation source of claim 13, wherein: The manifolds include two or more manifolds.

20. The radiation source of claim 13, wherein: In the manifolds, distances of the fluid paths passing through each of the manifolds are the same.

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