Collector flow ring

Abstract

Systems, apparatuses, and methods are provided for a collector flow ring (CFR) housing configured to mitigate accumulation of fuel debris in an extreme ultraviolet (EUV) radiation system. An example CFR housing may include a plurality of showerhead flow channel outlets configured to output a plurality of first gaseous fluid flows over a plurality of portions of a plasma facing surface of the CFR housing. The example CFR housing may also include a gutter purge flow channel outlet configured to output a second flow of gaseous fluid over a fuel debris receiving surface of the CFR housing. The example CFR housing may also include a shroud mounting structure configured to support the shroud assembly, a cooling flow channel configured to convey a fluid, and a plurality of optical metrology ports configured to receive a plurality of optical metrology tubes.

Description

[0001] Description of the case

[0002] This application is a divisional application of the invention patent application with international application number PCT / EP2020 / 085146, international application date December 9, 2020, date of entry into the Chinese national phase June 22, 2022, Chinese national application number 202080089564.0, and invention name “Collector Flow Ring”. Technical Field

[0003] The present disclosure relates to collectors and collector flow rings for extreme ultraviolet (EUV) radiation systems. Background Art

[0004] A lithographic apparatus is a machine that applies a desired pattern to a substrate (usually to a target portion of the substrate). A lithographic apparatus can be used, for example, in the manufacture of integrated circuits (ICs). In this case, a pattern forming device (or referred to as a mask or reticle) can be used to generate a circuit pattern to be formed on a single layer of the IC. The pattern can be transferred to a target portion (e.g., a portion comprising one or more dies) on a substrate (e.g., a silicon wafer). The transfer of the pattern is typically via imaging onto a layer of radiation-sensitive material (resist) disposed on the substrate. Typically, a single substrate will contain a network of adjacent target portions that are patterned continuously. Conventional lithographic apparatus includes a so-called stepper, in which each target portion is irradiated by exposing the entire pattern to the target portion at once; and a so-called scanner, in which each target portion is irradiated by scanning the pattern with a radiation beam in a given direction (scanning direction) while simultaneously scanning the target portion parallel or antiparallel (i.e., opposite) to the scan direction. The pattern can also be transferred from the pattern forming device to the substrate by imprinting the pattern onto the substrate.

[0005] Extreme ultraviolet (EUV) light (e.g., electromagnetic radiation having a wavelength of approximately 50 nanometers (nm) or less (sometimes also referred to as soft X-rays), and including light with a wavelength of approximately 13 nm) can be used in or with photolithography apparatuses to create extremely small features in or on substrates (e.g., silicon wafers). Methods of generating EUV light include, but are not necessarily limited to, converting a material including an element having emission lines in the EUV range (e.g., xenon (Xe), lithium (Li), or tin (Sn)) into a plasma state. For example, in one such method, known as laser-produced plasma (LPP), a plasma can be generated by irradiating a target material, which in the context of an LPP source is interchangeably referred to as fuel (e.g., in the form of droplets, slabs, ribbons, streams, or clusters of material), with an amplified beam of light, which can be referred to as a drive laser. For this process, the plasma is typically generated in a sealed container (e.g., a vacuum chamber) and monitored using various types of metrology equipment.

[0006] Within conventional tin-based radiation source containers, numerous features, such as protective hydrogen (H2), heat shielding, and precise shroud mounting, must also allow for measurement of the field of view (FOV) and droplet path clearance while preventing tin accumulation. Currently, there are numerous separate modules designed to address each of these issues individually. For example, active heat shields absorb unwanted heat flux, peripheral flow rings and collector modules provide shroud mounting and peripheral H2 flow, and cutouts within these modules allow for measurement of the FOV and deflection of stray light. However, there is no hardware on such conventional radiation source containers to provide showerhead flow beneath the flow vanes. Furthermore, there is no way to add (i) a single module or (ii) a modification to the current modules that would allow for increased showerhead flow protection. Summary of the Invention

[0007] The present disclosure describes various aspects of systems, apparatus, and methods for making and using a collector flow ring (CFR) housing configured to mitigate fuel debris accumulation, remove heat, and provide optical metrology in extreme ultraviolet (EUV) radiation systems, among other aspects.

[0008] In some aspects, the present disclosure describes a CFR housing configured to mitigate the accumulation of fuel debris in an EUV radiation system. The CFR housing may include a plurality of showerhead flow channel outlets configured to output a plurality of first gaseous fluid flows over a plurality of portions of a plasma-facing surface of the CFR housing. The CFR housing may also include a gutter wash flow channel outlet configured to output a second gaseous fluid flow over a fuel debris receiving surface of the CFR housing. The CFR housing may also include a shroud mounting structure configured to support a shroud assembly. The CFR housing may also include a cooling flow channel configured to convey a fluid configured to remove heat from at least a portion of the CFR housing during EUV radiation generation operation of the EUV radiation system. The CFR housing may also include a plurality of optical measurement ports configured to receive a plurality of optical measurement tubes.

[0009] In some aspects, the plurality of spray head flow channel outlets, the gutter wash flow channel outlets, and the plurality of optical metering ports are disposed in, ie, formed in, the body of the collector flow ring housing, which may be a single piece of material.

[0010] In some aspects, the present disclosure describes an EUV radiation source. The EUV radiation source may include a laser source configured to generate optical pulses configured to irradiate a fuel material at an irradiation location, the irradiated fuel material at the irradiation location configured to generate a plasma configured to emit EUV radiation. The EUV radiation source may also include a fuel source configured to deliver the fuel material to the irradiation location. The EUV radiation source may also include a CFR housing including a plurality of nozzle flow channel outlets configured to output a plurality of first gaseous fluid flows over a plurality of portions of a plasma-facing surface of the CFR housing. The CFR housing may also include a gutter wash flow channel outlet configured to output a second gaseous fluid flow over a fuel debris receiving surface of the CFR housing. The CFR housing may also include a shroud mounting structure configured to support a shroud assembly. The CFR housing may further include a cooling flow channel configured to convey a liquid fluid configured to remove heat from at least a portion of the CFR housing during EUV radiation generation operation of the EUV radiation system. The CFR housing may further include a plurality of optical measurement ports configured to receive a plurality of optical measurement tubes. The EUV radiation source may further include a controller configured to generate a first control signal configured to instruct the laser source to generate optical pulses. The controller may further be configured to generate a second control signal configured to instruct the fuel source to deliver a fuel material. The controller may further be configured to generate a third control signal configured to instruct the gaseous fluid source to control output of a plurality of first gaseous fluid flows from a plurality of nozzle flow channel outlets. The third control signal may further be configured to instruct the gaseous fluid source to control output of a second gaseous fluid flow from a gutter cleaning flow channel outlet. The controller may further be configured to generate a fourth control signal configured to instruct the liquid fluid source to control delivery of the liquid fluid in the cooling flow channel.

[0011] In some aspects, the present disclosure describes a method for manufacturing a CFR housing configured to mitigate fuel debris accumulation in an extreme ultraviolet (EUV) radiation system. The method may include forming a plurality of showerhead flow channel outlets configured to output a plurality of first gaseous fluid flows over a plurality of portions of a plasma-facing surface of the CFR housing. The method may also include forming a gutter wash flow channel outlet configured to output a second gaseous fluid flow over a fuel debris receiving surface of the CFR housing. The method may also include forming a shroud mounting structure configured to support a shroud assembly. The method may also include forming a cooling flow channel configured to convey a fluid configured to remove heat from at least a portion of the CFR housing during EUV radiation generation operation of the EUV radiation system. The method may also include forming a plurality of optical measurement ports configured to receive a plurality of optical measurement tubes.

[0012] Other features and the structure and operation of various aspects are described in detail below with reference to the accompanying drawings. It should be noted that the present disclosure is not limited to the specific aspects described herein. Such aspects are presented herein for illustrative purposes only. Based on the teachings contained herein, additional aspects will be apparent to those skilled in the relevant art. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] The accompanying drawings, which are incorporated herein and form a part of the specification, illustrate the disclosure and, together with the description, further serve to explain the principles of aspects of the disclosure and to enable one skilled in the relevant art to make and use aspects of the disclosure.

[0014] Figure 1A is a schematic diagram of an example reflective lithography apparatus according to some aspects of the present disclosure.

[0015] Figure 1B is a schematic diagram of an example transmissive lithography apparatus according to some aspects of the present disclosure.

[0016] Figure 2 According to some aspects of the present disclosure Figure 1A A more detailed schematic diagram of a reflective lithography apparatus is shown.

[0017] Figure 3 is a schematic diagram of an example lithocell according to some aspects of the present disclosure.

[0018] Figure 4 is a schematic diagram of an example radiation source for an example reflective lithography apparatus according to some aspects of the present disclosure.

[0019] Figure 5is a schematic diagram of an example collector flow ring according to some aspects of the present disclosure.

[0020] Figure 6A 、 Figure 6B 、 Figure 6C and Figure 6D is a schematic diagram of a portion of an example region of an example collector flow ring according to aspects of the present disclosure.

[0021] Figure 7 is a flow chart illustrating an example of a method for manufacturing a device or portion thereof according to some aspects of the present disclosure.

[0022] The features and advantages of the present disclosure will become more apparent from the detailed description set forth below in conjunction with the accompanying drawings, in which similar reference numerals always identify corresponding elements. In the drawings, similar reference numerals generally indicate identical, functionally similar, and / or structurally similar elements, unless otherwise indicated. In addition, generally, the leftmost digit(s) of a reference numeral identifies the drawing in which the reference numeral first appears. Unless otherwise indicated, the drawings provided throughout the disclosure should not be construed as being drawn to scale. DETAILED DESCRIPTION

[0023] This specification discloses one or more embodiments that incorporate the features of the present disclosure. The disclosed embodiment(s) merely illustrate the present disclosure. The scope of the present disclosure is not limited to the disclosed embodiment(s). The breadth and scope of the present disclosure are defined by the appended claims and their equivalents.

[0024] The described embodiment(s) and references in the specification to "one embodiment," "an embodiment," "an example embodiment," "an exemplary embodiment," etc. indicate that the described embodiment(s) may include a particular feature, structure, or characteristic, but every embodiment may not necessarily include the particular feature, structure, or characteristic. Furthermore, these phrases are not necessarily referring to the same embodiment. In addition, when a particular feature, structure, or characteristic is described in conjunction with an embodiment, it should be understood that it is within the knowledge of those skilled in the art to affect that feature, structure, or characteristic in conjunction with other embodiments, whether or not explicitly described.

[0025] For ease of description, spatially relative terms such as "below," "beneath," "above," "over," and the like may be used herein to describe the relationship of one element or feature to another element(s) or feature(s) illustrated in the figures. Spatially relative terms are intended to encompass different orientations of the device 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 should be interpreted accordingly.

[0026] As used herein, the term "about" indicates a value of a given amount that can vary based on a particular technology. Based on a particular technology, the term "about" can represent a value of a given amount that varies within, for example, 10-30% of a value (e.g., ±10%, ±20%, or ±30% of a value).

[0027] Overview

[0028] Compared to conventional radiation source containers, the present disclosure provides a radiation source container having a collector flow ring (CFR) that combines many separate modules into a single device, and in many cases, many features form part of a single machined piece, making the radiation source container modular. For example, the radiation source container disclosed herein moves the peripheral flow functionality from the radiation collector to the CFR, moves the shield mounting functionality from the radiation collector to the CFR, and adds a purge flow functionality to the CFR. In addition, the radiation source container disclosed herein adds a showerhead flow functionality to the CFR to keep plasma-facing surfaces clean and adds a purge flow functionality to prevent tin from overflowing the heating gutter below the flow vanes. In some aspects, by moving the peripheral flow ring away from the radiation collector and onto the CFR, and by combining these functions into a single device, the radiation source container disclosed herein provides improved maintainability and upgradeability as well as reduced hardware costs.

[0029] In some aspects, the CFR disclosed herein combines heat shielding, shield mounting, stray light deflection, channels for droplets, measurement FOV, gas protection for plasma-facing surfaces, flow guidance at the gutter to prevent overflow, and other functions disclosed herein into a single device. In some aspects, the CFR disclosed herein provides an exhaust path for measuring flow. In some aspects, the CFR disclosed herein provides space for a removable plug-in to clear tin write, referred to herein as a tin write plug-in. In some aspects, the CFR disclosed herein can handle higher power (e.g., 350W) than the power in a conventional radiation source container (e.g., 250W). In some aspects, the CFR disclosed herein can have a maintainability of less than about 2 hours and a lifespan of 7 years. In some aspects, the CFR disclosed herein provides guidance for the radiation collector to avoid interference and accurately position the radiation collector.

[0030] In some aspects, the CFR disclosed herein combines the following functionality into a single assembly: a peripheral flow ring geometry for separating the peripheral flow; a showerhead flow added to the plasma-facing surface to keep the surface clean and free of tin; a gutter purge flow added to prevent tin leakage from the flow vane gutter overflow; providing showerhead and gutter flow and providing non-uniformity of less than about 3%; a measurement FOV for multiple measurement ports (e.g., 13 measurement ports); active cooling heat dissipation; a shield mount; stray light deflection; a placeholder for a tin write plug design (e.g., providing the ability to upgrade the tin write plug); a flexible seal that contains the measurement flow exhaust and can accommodate misalignment of the CFR position; and precisely manufactured guide rails to allow the radiation collector to have a path for mounting and alignment within about 1 mm, 100 microns, about 10 microns, or about 1 micron.

[0031] In some aspects, the CFRs disclosed herein combine the following features:

[0032] 1. A single device that can combine the functionality of the above modules and include the new functionality of showerhead flow, thereby combining thermal cooling, gas flow and precision alignment into a single device.

[0033] 2. Showerhead flow: H2 flow protection (Peclet) on the plasma facing surface to keep the tin clean.

[0034] 3. Gutter cleaning flow: A flow used to prevent the tin flowing in the flow blade gutter from overflowing.

[0035] 4. Common plenum for sprinkler and gutter flow: Predictable and uniform flow exits from a common plenum and a single H2 inlet source by passive means.

[0036] 5. A single device design that combines thermal shielding, precision mounting, collector guidance, flow delivery, droplet channels, and optical FOV channels.

[0037] 6. Collector guides: Guides that steer the radiation collector along a safe path into a precisely positioned mounting position (eg, within a tolerance of about 1 mm, 100 microns, about 10 microns, or about 1 micron).

[0038] 7. Gauge flow seal: A resistant seal capable of closing the gap between the gauge tube in the CFR and the inner radiation source container wall within the position tolerance range of the CFR (e.g., within a tolerance of about 1 mm, 100 microns, about 10 microns, or about 1 micron).

[0039] 8. Cooling water channels within the H2 surge chamber with a combined O-ring and gasket sealing structure, allowing the heat path to be shorter than conventional designs.

[0040] 9. Self-centering precision shield installation. The shield can be configured to protect fuel targets (eg, droplets).

[0041] 10. Shrink fit metering tube sealing, using an inserted metering tube to seal penetrations that may occur as a result of drilling operations to fit the tube (e.g., shrink fit tubing used to seal flow between plenums).

[0042] 11. A retardation-restricted flow configuration that delivers low non-uniformity using a single inlet and a common plenum.

[0043] 12. Stray light scattering in measuring tubes with custom threads.

[0044] The radiation source containers and CFRs disclosed herein have many advantages and benefits. For example, various aspects of the present disclosure provide: modularity (e.g., improved maintainability, improved upgradeability); improved performance (e.g., more functionality included in a single device); improved usability (e.g., less tin deposition and faster maintainability than conventional radiation source containers); and reduced cost (e.g., building the peripheral flow functionality into the CFR can be less expensive than building the peripheral flow functionality into the radiation collector in conventional designs).

[0045] Before describing these aspects in greater detail, however, it is instructive to present an example environment in which aspects of the present disclosure may be implemented.

[0046] Example lithography system

[0047] Figure 1A and Figure 1B are schematic diagrams of lithographic apparatus 100 and lithographic apparatus 100', respectively, in which aspects of the present disclosure may be implemented. Figure 1A and Figure 1B As shown, the lithographic apparatus 100 and 100' are shown from a perspective (e.g., a side view) that is orthogonal to the XZ plane (e.g., with the X-axis pointing to the right and the Z-axis pointing upward), while the patterning device MA and substrate W are presented from an additional perspective (e.g., a top view) that is orthogonal to the XY plane (e.g., with the X-axis pointing to the right and the Y-axis pointing upward).

[0048] The lithographic apparatus 100 and the lithographic apparatus 100 ′ each include an illumination system (illuminator) IL configured to condition a radiation beam B (e.g., a deep ultraviolet (DUV) radiation beam or an extreme ultraviolet (EUV) radiation beam); a support structure (e.g., a mask table) MT configured to support a patterning device (e.g., a mask, a reticle, or a dynamic patterning device) MA and connected to a first positioner PM configured to precisely position the patterning device MA; and a substrate holder (e.g., a wafer stage) WT, such as a substrate table, configured to hold a substrate (e.g., a resist-coated wafer) W and connected to a second positioner PW configured to precisely position the substrate W. The lithographic apparatus 100 and 100 ′ further has a projection system PS configured to project a pattern imparted to the radiation beam B by the patterning device MA onto a target portion C (e.g., a portion comprising one or more dies) of the substrate W. In lithographic apparatus 100, patterning device MA and projection system PS are reflective. In lithographic apparatus 100', patterning device MA and projection system PS are transmissive.

[0049] The illumination system IL may include various types of optical components for directing, shaping or controlling the radiation beam B, such as refractive, reflective, catadioptric, magnetic, electromagnetic, electrostatic or other types of optical components, or any combination thereof.

[0050] The support structure MT holds the patterning device MA in a manner that depends on the orientation of the patterning device MA relative to the reference frame, the design of at least one of the lithographic apparatuses 100 and 100', and other conditions, such as whether the patterning device MA is held in a vacuum environment. The support structure MT can use mechanical, vacuum, electrostatic, or other clamping techniques to hold the patterning device MA. The support structure MT can be, for example, a frame or a table that can be fixed or movable as desired. By using sensors, the support structure MT can ensure that the patterning device MA is in a desired position, for example, relative to the projection system PS.

[0051] The term "patterning device" MA should be broadly interpreted as referring to any device that can be used to impart a pattern in the cross-section of a radiation beam B so as to create a pattern in a target portion C of the substrate W. The pattern imparted to the radiation beam B may correspond to a specific functional layer in the device being created in the target portion C to form an integrated circuit.

[0052] The patterning device MA may be transmissive (e.g. Figure 1B lithographic apparatus 100') or reflective (as in Figure 1Alithographic apparatus 100). Examples of patterning devices MA include reticles, masks, programmable mirror arrays, or programmable LCD panels. Masks include types such as binary, alternating phase shift, or attenuated phase shift, as well as various hybrid mask types. Examples of programmable mirror arrays employ a matrix arrangement of small mirrors, each of which can be individually tilted to reflect an incoming radiation beam in different directions. The tilted mirrors impart a pattern in the radiation beam B, which is reflected by the matrix of small mirrors.

[0053] The term "projection system" PS may include any type of projection system, including refractive, reflective, catadioptric, magnetic, electromagnetic, and electrostatic optical systems, or any combination thereof, appropriate to the exposure radiation used, or to other factors, such as the use of an immersion liquid or the use of a vacuum on the substrate W. A vacuum environment may be used for EUV or electron beam radiation, as other gases may absorb too much radiation or electrons. Therefore, a vacuum environment may be provided to the entire beam path with the aid of vacuum walls and a vacuum pump.

[0054] The lithographic apparatus 100 and / or the lithographic apparatus 100' may be of a type having two (dual-stage) or more substrate tables WT (and / or two or more mask tables). In such a "multi-stage" machine, additional substrate tables WT may be used in parallel, or preparatory steps may be performed on one or more tables while one or more other substrate tables WT are being used for exposure. In some cases, the additional tables may not be substrate tables WT.

[0055] The lithographic apparatus may also be of a type in which at least a portion of the substrate may be covered with a liquid having a relatively high refractive index (e.g., water) to fill the space between the projection system and the substrate. Immersion liquid may also be applied to other spaces in the lithographic apparatus, such as the space between the mask and the projection system. Immersion techniques provide for increasing the numerical aperture of the projection system. As used herein, the term "immersion" does not mean that structures such as the substrate are necessarily submerged in the liquid, but only means that the liquid is located between the projection system and the substrate during exposure.

[0056] refer to Figure 1A and Figure 1B , the illuminator IL receives a radiation beam from a radiation source SO. For example, when the radiation source SO is an excimer laser, the radiation source SO and the lithographic apparatus 100, 100' may be separate physical entities. In this case, the radiation source SO is not considered to form part of the lithographic apparatus 100 or 100', and the radiation beam B is delivered to the lithographic apparatus 100 or 100' by means of a beam delivery system BD comprising, for example, suitable directing mirrors and / or a beam expander (e.g., in FIG. Figure 1B100 ′.

[0057] The illumination system IL may comprise an adjuster AD for adjusting the angular intensity distribution of the radiation beam (e.g. Figure 1B Typically, at least the outer and / or inner radial extent of the intensity distribution in a pupil plane of the illuminator (commonly referred to as "σ-outer" and "σ-inner", respectively) can be adjusted. Furthermore, the illumination system IL may include various other components (e.g., Figure 1B The illumination system IL may be used to condition the radiation beam B to have a desired uniformity and intensity distribution in its cross-section.

[0058] Reference Figure 1A , a radiation beam B is incident on a patterning device (e.g., a mask) MA held on a support structure (e.g., a mask table) MT and is patterned by the patterning device MA. In the lithographic apparatus 100, the radiation beam B is reflected from the patterning device MA. After being reflected from the patterning device MA, the radiation beam B passes through a projection system PS, which focuses the radiation beam B onto a target portion C of the substrate W. With the aid of a second positioner PW and a position sensor IF2 (e.g., an interferometer, a linear encoder, or a capacitive sensor), the substrate table WT can be precisely moved (e.g., in order to position a different target portion C in the path of the radiation beam B). Similarly, a first positioner PM and a further position sensor IF1 (e.g., an interferometer, a linear encoder, or a capacitive sensor) can be used to precisely position the patterning device MA relative to the path of the radiation beam B. The patterning device MA and the substrate W can be aligned using mask alignment marks M1 and M2 and substrate alignment marks P1 and P2.

[0059] Reference Figure 1B , radiation beam B is incident on the patterning device MA, which is held on the support structure MT, and is patterned by the patterning device MA. After passing through the patterning device MA, the radiation beam B passes through the projection system PS, which focuses the beam onto a target portion C of the substrate W. The projection system has a pupil PPU that is conjugate with the illumination system pupil IPU. Portions of the radiation emanate from the intensity distribution at the illumination system pupil IPU and pass through the mask pattern without being affected by diffraction at the mask pattern, generating an image of the intensity distribution at the illumination system pupil IPU.

[0060] The projection system PS projects an image MP' of the mask pattern MP onto a photoresist layer coated on the substrate W, wherein the image MP' is formed by a diffraction beam generated from the marking pattern MP by radiation from an intensity distribution. For example, the mask pattern MP may comprise an array of lines and spaces. The diffraction of the radiation at the array is different from the zeroth order diffraction, generating a steered diffraction beam with a change of direction in a direction perpendicular to the lines. The undiffracted beam, the so-called zeroth order diffraction beam, passes through the pattern without any change in the propagation direction. The zeroth order diffraction beam passes through an upper lens or an upper lens group in the projection system PS upstream of a pupil conjugate PPU of the projection system PS to reach the pupil conjugate PPU. The part of the intensity distribution in the plane of the pupil conjugate PPU and associated with the zeroth order diffraction beam is an image of the intensity distribution in the illumination system pupil IPU of the illumination system IL. The aperture device PD is, for example, arranged or substantially arranged at a plane comprising the pupil conjugate PPU of the projection system PS.

[0061] The projection system PS is arranged to capture not only the zeroth order diffraction beam, but also the first order or first and higher order diffraction beams (not shown) by means of a lens or lens group L. In some embodiments, dipole illumination for imaging a line pattern extending in a direction perpendicular to the line can be used to exploit the resolution enhancement effect of dipole illumination. For example, the first order diffraction beam interferes with the corresponding zeroth order diffraction beam at the level of the substrate W to create an image of the line pattern MP at the highest possible resolution and process window (i.e., the available depth of focus combined with a tolerable exposure dose deviation). In some embodiments, astigmatic aberrations can be reduced by providing radiating poles (not shown) in opposite quadrants of the illumination system pupil IPU. Furthermore, in some embodiments, astigmatic aberrations can be reduced by blocking the zeroth order beam in the pupil conjugate PPU of the projection system associated with the radiating poles in the opposite quadrant. This is described in more detail in U.S. Patent No. 7,511,799, published on March 31, 2009, which is incorporated herein by reference in its entirety.

[0062] With the help of a second positioner PW and a position sensor IF (e.g. an interferometric device, a linear encoder or a capacitive sensor), the substrate table WT can be precisely moved (e.g. to position a different target portion C in the path of the radiation beam B). Similarly, the first positioner PM and another position sensor ( Figure 1B ) can be used to accurately position the patterning device MA relative to the path of the radiation beam B (e.g. after mechanical retrieval from a mask library or during scanning).

[0063] Typically, movement of the mask table MT may be achieved with the aid of a long-stroke module (coarse positioning) and a short-stroke module (fine positioning), which form part of the first positioner PM. Similarly, movement of the substrate table WT may be achieved using a long-stroke module and a short-stroke module, which form part of the second positioner PW. In the case of a stepper (as opposed to a scanner), the mask table MT may be connected to the short-stroke actuator only or may be fixed. The patterning device MA and the substrate W may be aligned using mask alignment marks M1, M2 and substrate alignment marks P1, P2. Although the substrate alignment marks (as shown) occupy dedicated target portions, they may be located in the space between target portions (called lane alignment marks). Similarly, where more than one die is provided on the patterning device MA, the mask alignment marks may be located between the dies.

[0064] The mask table MT and patterning device MA can be in a vacuum chamber V, where an in-vacuum robot IVR can be used to move the patterning device (e.g., mask) into and out of the vacuum chamber. Alternatively, when the support structure MT and patterning device MA are outside the vacuum chamber, an out-of-vacuum robot can be used for various transport operations, similar to the in-vacuum robot IVR. Both the in-vacuum and out-of-vacuum robots need to be calibrated for smooth transfer of any payload (e.g., mask) to the fixed kinematic support of the transfer station.

[0065] The lithographic apparatuses 100 and 100 ′ may be used in at least one of the following modes:

[0066] 1. In step mode, the support structure MT and substrate table WT are held substantially stationary while an entire pattern imparted to the radiation beam B is projected at once onto a target portion C (i.e. a single static exposure). The substrate table WT is then shifted in the X and / or Y direction so that a different target portion C can be exposed.

[0067] 2. In scan mode, the support structure MT and substrate table WT are scanned synchronously while a pattern imparted to the radiation beam B is projected onto a target portion C (i.e., a single dynamic exposure). The velocity and direction of the substrate table WT relative to the support structure (e.g., mask table) MT may be determined by the (de)magnification and image reversal characteristics of the projection system PS.

[0068] 3. In another mode, the support structure MT is held substantially stationary so as to hold the programmable patterning device MA, and the substrate table WT is moved or scanned while a pattern imparted to the radiation beam B is projected onto a target portion C. A pulsed radiation source SO may be employed, and the programmable patterning device updated as required after each movement of the substrate table WT or between successive radiation pulses during a scan. This mode of operation can be readily applied to maskless lithography utilizing a programmable patterning device MA, such as a programmable mirror array.

[0069] Combinations and / or variations of the described modes of use or entirely different modes of use may also be employed.

[0070] In another aspect, the lithographic apparatus 100 includes an EUV source configured to generate an EUV radiation beam for EUV lithography. Typically, the EUV source is configured in a radiation system, and a corresponding illumination system is configured to condition the EUV radiation beam of the EUV source.

[0071] Figure 2 The lithographic apparatus 100 is shown in more detail, comprising a radiation source SO (source collector device), an illumination system IL and a projection system PS. Figure 2 As shown, the lithographic apparatus 100 is illustrated from a perspective (eg, a side view) perpendicular to the XZ plane (eg, with the X-axis pointing to the right and the Z-axis pointing upward).

[0072] The radiation source SO is constructed and arranged so that a vacuum environment can be maintained in the enclosed structure 220. The radiation source SO includes a source chamber 211 and a collector chamber 212, and is configured to generate and transmit EUV radiation. The EUV radiation can be generated by a gas or vapor (e.g., xenon (Xe) gas, lithium (Li) vapor, or tin (Sn) vapor, in which an EUV radiation emitting plasma 210 is generated to emit radiation in the EUV range of the electromagnetic spectrum). For example, the EUV radiation emitting plasma 210 (at least partially ionized) can be generated by, for example, an electric discharge or a laser beam. In order to effectively generate radiation, a partial pressure of Xe gas, Li vapor, Sn vapor, or any other suitable gas or vapor of, for example, 10 Pascals (Pa) can be used. In some aspects, an excited tin (Sn) plasma is provided to generate EUV radiation.

[0073] Radiation emitted by EUV radiation emitting plasma 210 is passed from source chamber 211 into collector chamber 212 via an optional gas barrier or contamination trap 230 (also referred to in some cases as a contamination barrier or foil trap) located in or behind an opening in source chamber 211. Contamination trap 230 may include a channel structure. Contamination trap 230 may also include a gas barrier or a combination of a gas barrier and a channel structure. Contamination trap 230, as further described herein, includes at least a channel structure.

[0074] The collector chamber 212 may include a radiation collector CO (e.g., a buncher or collector), which may be a so-called grazing incidence collector. The radiation collector CO has an upstream radiation collector side 251 and a downstream radiation collector side 252. Radiation passing through the collector CO may be reflected off the grating spectral filter 240 to be focused at a virtual source point IF. The virtual source point IF is often referred to as an intermediate focus, and the source collector apparatus is arranged so that the virtual source point IF is located at or near the opening 219 in the enclosure 220. The virtual source point IF is an image of the EUV radiation emitting plasma 210. The grating spectral filter 240 is particularly useful for suppressing infrared (IR) radiation.

[0075] The radiation then passes through the illumination system IL, which may include a faceted field mirror arrangement 222 and a faceted pupil mirror arrangement 224 arranged to provide a desired angular distribution of the radiation beam 221 at the patterning device MA, and a desired uniformity of radiation intensity at the patterning device MA. When the radiation beam 221 reflects at the patterning device MA, which is held by the support structure MT, a patterned beam 226 is formed, and the patterned beam 226 is imaged by the projection system PS via reflective elements 228, 229 onto a substrate W held by a wafer stage or substrate table WT.

[0076] There may typically be more elements present in the illumination system IL and the projection system PS than shown. Depending on the type of lithographic apparatus, a grating spectral filter 240 may optionally be present. Additionally, there may be more than Figure 2 More reflectors are shown, such as Figure 2 Compared to what is shown, there may be 1 to 6 additional reflective elements present in projection system PS.

[0077] like Figure 2As shown, the radiation collector CO is depicted as a nested collector with grazing incidence reflectors 253, 254 and 255, just as an example of a collector (or collector mirror). The grazing incidence reflectors 253, 254 and 255 are arranged axisymmetrically around the optical axis O, and this type of radiation collector CO is preferably used in combination with a discharge produced plasma (DPP) source.

[0078] Example Lithography Cell

[0079] Figure 3 A lithocell 300 is shown, sometimes also referred to as a lithocell or cluster. The litho apparatus 100 or 100' may form part of the lithocell 300. The lithocell 300 may also include one or more devices for performing pre-exposure and post-exposure processes on the substrate. For example, these devices include a spin coater SC for depositing a resist layer, a developer DE for developing the exposed resist, a cooling plate CH, and a baking plate BK. A substrate handler RO (robot) picks up substrates from input / output ports I / O1, I / O2, moves them between different processing devices, and delivers them to the loading bay LB of the litho apparatus 100 or 100'. These devices, generally referred to as tracks, are under the control of a track control unit TCU, which is itself controlled by a supervisory control system SCS, which also controls the litho apparatus via a litho control unit LACU. Thus, different devices can be operated to maximize throughput and processing efficiency.

[0080] Example radiation source

[0081] An example of a radiation source SO for an exemplary reflective lithography exposure apparatus is shown in FIG. Figure 4 As shown in Figure 4 As shown, the radiation source SO is shown from a perspective perpendicular to the XY plane described below (eg, a top view).

[0082] Figure 4The radiation source SO shown is of a type that may be referred to as a laser-generated plasma (LPP) source. A laser system 401, which may, for example, include a carbon dioxide (CO2) laser, is arranged to deposit energy into a fuel target 403', such as one or more discrete tin (Sn) droplets provided from a fuel target generator 403 (e.g., a fuel emitter, a droplet generator), via one or more laser beams 402. In some aspects, the laser system 401 may be a pulsed, continuous wave, or quasi-continuous wave laser, or may operate in a pulsed, continuous wave, or quasi-continuous wave laser manner. The trajectory of the fuel target 403' (e.g., a droplet) emitted from the fuel target generator 403 may be parallel to the X-axis. In some aspects, the one or more laser beams 402 propagate in a direction parallel to the Y-axis, which is perpendicular to the X-axis. The Z-axis is perpendicular to both the X-axis and the Y-axis and generally extends into (or out of) the plane of the page, although in other aspects, other configurations are used. In some embodiments, the laser beam 402 may propagate in a direction other than parallel to the Y-axis, ie, in a direction other than orthogonal to the X-axis direction of the fuel target trajectory.

[0083] Although tin is mentioned in the following description, any suitable target material may be used. The target material may be, for example, in liquid form and may be, for example, a metal or alloy. The fuel target generator 403 may include a nozzle configured to direct tin, for example, in the form of a fuel target 403' (e.g., discrete droplets) along a trajectory toward the plasma formation region 404. Throughout the remainder of the specification, references to "fuel," "fuel target," or "fuel droplets" should be understood to refer to the target material (e.g., droplets) emitted by the fuel target generator 403. The fuel target generator 403 may include a fuel emitter. One or more laser beams 402 are incident on the target material (e.g., tin) at the plasma formation region 404. The deposition of laser energy into the target material generates a plasma 407 at the plasma formation region 404. Radiation, including EUV radiation, is emitted from the plasma 407 during de-excitation and recombination of ions and electrons of the plasma.

[0084] The EUV radiation is collected and focused by a collector 405 (e.g., radiation collector CO). In some aspects, the collector 405 can include a near-normal incidence radiation collector (sometimes more generally referred to as a normal incidence radiation collector). The collector 405 can be a multi-layer structure arranged to reflect EUV light (e.g., EUV radiation having a desired wavelength, such as approximately 13.5 nm). According to some aspects, the collector 405 can have an elliptical configuration with two focal points. As discussed herein, the first focal point can be at the plasma formation region 404, and the second focal point can be at the intermediate focus IF.

[0085] In some aspects, the laser system 401 can be located at a relatively long distance from the radiation source SO. In this case, one or more laser beams 402 can be delivered from the laser system 401 to the radiation source SO with the aid of a beam delivery system (not shown) including, for example, suitable directing mirrors and / or beam expanders and / or other optical devices. The laser system 401 and the EUV light source SO can be considered together as a radiation system.

[0086] The radiation reflected by the collector 405 forms a radiation beam B. The radiation beam B is focused at one point (ie, the intermediate focus IF) to form an image of the plasma formation region 404, which acts as a virtual radiation source for the illumination system IL (see FIG. Figure 2 The point at which the radiation beam B is focused may be referred to as an intermediate focus IF (intermediate focus 406). The radiation source SO is arranged such that the intermediate focus IF is located at or near an opening 408 in an enclosing structure 409 of the radiation source SO.

[0087] A radiation beam B is passed from a radiation source SO into an illumination system IL which is configured to condition the radiation beam B. The radiation beam B is passed from the illumination system IL and is incident on a patterning device MA held by a support structure MT. The patterning device MA reflects and patterns the radiation beam B. After reflection from the patterning device MA, the patterned radiation beam B enters the projection system PS. The projection system comprises a plurality of mirrors which are configured to project the radiation beam B onto a substrate W held by a substrate table WT. The projection system PS may apply a reduction factor to the radiation beam so as to form an image with features which are smaller than corresponding features on the patterning device MA. For example, a reduction factor of 4 may be applied. Although the projection system PS is Figure 2 Although shown with two mirrors, the projection system may include any number of mirrors (eg, six mirrors).

[0088] The radiation source SO may include Figure 4 For example, a spectral filter may be provided in the radiation source SO. The spectral filter may be substantially transmissive to EUV radiation but substantially blocking radiation of other wavelengths, such as infrared radiation.

[0089] The radiation source SO (or radiation system) further includes a fuel target imaging system for obtaining an image of a fuel target (e.g., a droplet) in the plasma formation region 404, or more specifically, a shadow image of the fuel target. The fuel target imaging system can detect light diffracted from the edge of the fuel target. References to fuel target images hereinafter should also be understood to refer to shadow images of the fuel target or diffraction patterns caused by the fuel target.

[0090] The fuel target imaging system may include a photodetector, such as a CCD array or a CMOS sensor, but it will be appreciated that any imaging device suitable for obtaining an image of the fuel target may be used. It will be appreciated that the fuel target imaging system may also include an optical component, such as one or more lenses, in addition to the photodetector. For example, the fuel target imaging system may include a camera 410, for example, a combination of a photosensor (or: photodetector) and one or more lenses. The optical components may be selected so that the photosensor or camera 410 obtains near-field images and / or far-field images. The camera 410 may be positioned at any suitable location within the radiation source SO from which the camera has a line of sight to the plasma formation region 404 and one or more markers ( Figure 4 (not shown). However, it may be desirable to position camera 410 away from the propagation path of one or more laser beams 402 and away from the trajectory of fuel targets launched by fuel target generator 403 to avoid damage to camera 410. According to certain aspects, camera 410 is configured to provide images of the fuel targets to controller 411 via connection 412. Connection 412 is shown as a wired connection, although it should be understood that connection 412 (and other connections mentioned herein) can be implemented as a wired connection, a wireless connection, or a combination thereof.

[0091] like Figure 4 As shown in FIG, the radiation source SO may include a fuel target generator 403 configured to generate and launch fuel targets 403′ (such as discrete tin droplets) toward a plasma formation region 404. The radiation source SO may also include a laser system 401 configured to strike one or more of the fuel targets 403′ with one or more laser beams 402 to generate a plasma 407 at the plasma formation region 404. The radiation source SO may also include a collector 405 (i.e., a radiation collector CO) configured to collect radiation emitted by the plasma 407. In some aspects, the collector flow ring CFR ( Figure 4 A collector flow ring (not shown) may be positioned adjacent to the collector 405 to mitigate, among other features, the accumulation of fuel debris (e.g., tin) in the radiation source SO. The collector flow ring CFR may be positioned along an axis parallel to the X-axis (e.g., near the trajectory of the fuel target 403' emitted from the fuel target).

[0092] Example Collector Flow Ring

[0093] Figure 5 An exploded view of an example collector flow ring (CFR) 500 is shown, which may be arranged to be coupled to a radiation collector CO (eg, Figure 4405) adjacent to the collector 405 shown in FIG. 406 to mitigate the accumulation of fuel debris (e.g., tin) in the radiation source SO. The CFR 500 can be positioned to direct flow into the collector 405, such as to mitigate the accumulation of fuel debris (e.g., tin debris) in the radiation source SO. In some aspects, the total weight of the example CFR 500 can be less than about 200 kilograms (kg) or less than about 150 kg. In some aspects, without the cooling fluid supply 506 and the gas supply 524, the overall dimensions of the example CFR 500 can be approximately 1.2 m×1.0 m×90 mm (e.g., the thickness of the CFR housing 502). In some aspects, with the cooling fluid supply 506 and the gas supply 524, the overall dimensions of the example CFR 500 can be approximately 1.2 m×1.0 m×800 mm, although other dimensions are used in other embodiments.

[0094] In some aspects, the example CFR 500 may include a CFR housing 502 configured to mitigate the presence of fuel debris (eg, tin) in an EUV radiation system (eg, Figure 1A and Figure 4 In some aspects, the CFR housing 502 can be formed of or include aluminum (Al). In some aspects, the CFR housing 502 can include a coating of at least one material selected from the group consisting of titanium nitride (TiN), tin (Sn), and nickel (Ni).

[0095] In some aspects, the CFR housing 502 can include a plurality of showerhead flow channel outlets configured to output a plurality of first gaseous fluid flows (e.g., H2 flows) over portions of a plasma-facing surface of the CFR housing 502. In some aspects, the CFR housing 502 can include a gutter wash flow channel outlet configured to output a second gaseous fluid flow (e.g., H2 flow) over a fuel debris receiving surface of the CFR housing 502. In some aspects, the plurality of showerhead flow channel outlets and the gutter wash flow channel outlet can be configured to be fluidly coupled to a gaseous fluid plenum configured to generate an overall non-uniformity in gaseous fluid flow between the plurality of first gaseous fluid flows and the second gaseous fluid flow of less than about 5%, less than about 3%, or less than about 1%.

[0096] In some aspects, the CFR housing 502 can include a shroud mounting structure configured to support a shroud assembly 520 (e.g., including, but not limited to, a ceramic shroud). The shroud assembly 520 can be configured to protect a fuel target (e.g., fuel target 403'). In some aspects, the CFR housing 502 can include a cooling flow channel configured to convey a fluid (e.g., water, deionized water, a refrigerant, a nanofluid including nanoparticles, or any other suitable fluid) configured to remove heat from at least a portion of the CFR housing 502 during EUV radiation generation operation of the EUV radiation system. In some aspects, the CFR housing 502 can include a plurality of optical measurement ports configured to receive a plurality of optical measurement tubes. In some aspects, the CFR housing 502 can include a plurality of thermal measurement channels configured to support a plurality of thermal measurement devices (e.g., thermocouple-based devices). In some aspects, the CFR housing 502 can include a weight reduction cavity 522 configured to reduce the overall mass of the CFR housing 502 and modify the center of gravity of the CFR housing 502 (eg, to balance the CFR housing 502 ).

[0097] In some aspects, the CFR housing 502 can include a plurality of collector rail mounting structures 540 configured to attach to a plurality of collector rails 542. In some aspects, the plurality of collector rails 542 can be configured to divert the radiation collector CO along a safe path relative to the collector, such as Figure 4 The example CFR 500 may include a plurality of CFR mounts 544 configured to attach to the plurality of collector rails 542 and mount the example CFR 500 to the radiation collector CO (see FIG. Figure 2 ).

[0098] In some aspects, the example CFR 500 can include a cooling fluid channel assembly 504 (including, but not limited to, cooling fluid channels and cooling fluid connections, valves, or both), a cooling fluid supply 506 (e.g., a water supply), and a cooling fluid channel cover 508. In some aspects, the cooling fluid channel assembly 504 can include cooling fluid channels within the gas plenum with a combined O-ring and gasket sealing structure, allowing for shorter thermal paths than conventional designs. In some aspects, the cooling fluid channel assembly 504 provides active cooling to dissipate heat from the example CFR 500, the CFR housing 502, or any components included therein or mechanically connected thereto. In some aspects, the cooling fluid channel assembly 504 can be bolted to a flat interface surface of the CFR housing 502. In some aspects, the bottom surface of the water channel bottom surface can also be tin-coated to provide increased heat transfer benefits.

[0099] In some aspects, the example CFR 500 can include a tin-repellent sheet 510. Optionally, the example CFR 500 can include a tin-write plug 512 or a placeholder for a tin-write plug design that provides the ability to upgrade the tin-write plug 512.

[0100] In some aspects, the example CFR 500 can include a shroud assembly 520 that can be a precision shroud mount configured for self-centering. In some aspects, the example CFR 500 can include a gaseous fluid source, such as a gas supply 524 (e.g., an H2 supply). In some aspects, the example CFR 500 can include a thermocouple access panel 526 that can be removably attached to the CFR housing 502 and configured to provide access to a plurality of calorimetric devices disposed in a plurality of calorimetric channels in the CFR housing 502. For example, the example CFR 500 can include four thermocouple devices (e.g., two thermocouple devices on each side of the example CFR 500).

[0101] In some aspects, the example CFR 500 can include a plurality of optical measurement tubes 528 configured to provide measurement FOVs for a plurality of optical measurement ports (e.g., thirteen measurement ports) disposed through the CFR housing 502. In some aspects, the example CFR 500 can include a plurality of optical measurement face seals 530, which can be resistant seals configured to close gaps between the inner surface of the CFR housing 502 and the optical measurement tubes 528 within a positional tolerance of the example CFR 500 (e.g., within a tolerance of approximately 1 mm, 100 microns, approximately 10 microns, or approximately 1 micron). In some aspects, the plurality of optical measurement face seals 530 can be flexible seals that contain the measurement flow exhaust and can accommodate misalignment of the position of the example CFR 500. In some aspects, the example CFR 500 can provide a shrink fit optical tube seal that uses an inserted optical tube 528 to seal penetrations that may occur due to drilling operations to fit the optical tube 528 (e.g., shrink fit tubing for sealing flow between plenums).

[0102] Figure 6A 、 Figure 6B 、 Figure 6C and Figure 6D is a schematic diagram of a portion of an example region of an example CFR 600 according to some aspects of the present disclosure.

[0103] Figure 6A A cutaway perspective portion of a first example region of an example CFR 600 including a CFR housing 602 according to some aspects of the present disclosure is illustrated. In some aspects, the overall dimensions of the CFR housing 602 can be approximately 1.2 m x 1.0 m x 90 mm, although various other suitable dimensions are used in other embodiments.

[0104] The CFR housing 602 may include a plurality of showerhead flow channel outlets 604 configured to output a plurality of first gaseous fluid flows over portions of a plasma-facing surface 602 a of the CFR housing 602. The CFR housing 602 may include a gutter purge flow channel outlet 606 configured to output a second gaseous fluid flow over a fuel debris receiving surface 602 b of the CFR housing 602.

[0105] The CFR housing 602 may include a cooling flow channel 612 configured to convey a liquid fluid configured to remove heat from at least a portion of the CFR housing 602 during EUV radiation generating operation of the EUV radiation system. The CFR housing 602 may include a cooling fluid channel cover 614 configured to (e.g., at least partially) seal the cooling flow channel 612.

[0106] The CFR housing 602 can include a plurality of optical metering ports 616 configured to receive and support a plurality of optical metering tubes 618. In some aspects, the plurality of sprinkler flow channel outlets 604, the gutter wash flow channel outlets 606, and the plurality of optical metering ports 616 can be disposed on a body of the CFR housing 602, which can be a single component or part.

[0107] The CFR shell 602 may include a peripheral flow channel outlet 620 configured to output a peripheral gaseous fluid flow over the surface of a peripheral flow ring 622 of the CFR shell 602. The peripheral flow ring 622 may include a mesh ring to provide restriction to the peripheral gaseous fluid flow to promote uniformity. A peripheral skin panel 624 may be welded to the bottom of the CFR shell 602 with an aerodynamically shaped boss to provide stiffness and a constant gap thickness so that the peripheral gaseous fluid flow becomes fully developed and uniform.

[0108] In some aspects, CFR housing 602 can include a plurality of collector rail mounting structures configured to attach to a plurality of collector rails (such as collector rails 626 ).

[0109] Figure 6B 1 illustrates a cutaway perspective portion of a second example region of an example CFR 600 according to some aspects of the present disclosure. Figure 6B As shown, the CFR housing 602 can include a gas supply 628 (eg, a source of gaseous fluid, such as an H 2 supply).

[0110] Figure 6C 1 illustrates a cutaway perspective portion of a third example region of an example CFR 600 according to some aspects of the present disclosure. Figure 6C As shown, the CFR housing 602 can include an optical metrology face seal 630 configured to attach one of the plurality of optical metrology tubes 618 to the CFR housing 602 .

[0111] Figure 6D FIG. 6 illustrates a portion of a fourth example region of an example CFR 600 according to aspects of the present disclosure. Figure 6DAs shown, the CFR housing 602 may include a showerhead flow distribution plenum 680, which may be a first chamber configured to receive a single inlet and spread the flow as far as possible around the CFR, the single inlet being fluidly connected to the gas supply 628. The CFR housing 602 may include a showerhead flow expansion plenum 682, which may be configured to slow the flow, provide a pressure reservoir for the outlet flow, and assist in distribution for the most distant flow points. Although not shown in FIG. Figure 6D , but the nozzle flow distribution plenum 680 can be fluidly coupled to the nozzle flow expansion plenum 682. The CFR housing 602 can include a peripheral flow distribution plenum 684 that can be configured to receive flow from the single inlet and expand it as much as possible. The peripheral flow distribution plenum 684 can be machined out of the bottom and sealed with an aluminum skin panel. The CFR housing 602 can include a peripheral flow expansion plenum 686 that can have functions substantially similar to the nozzle flow expansion plenum 682 (e.g., decelerating the gas, expanding the gas to provide a constant pressure reservoir, and assisting in distribution). The peripheral flow expansion plenum 686 can be machined out and sealed with a peripheral skin panel 624 (e.g., an aluminum skin panel) on the bottom of the CFR housing 602.

[0112] like Figure 6D As further shown, the plurality of nozzle flow channel outlets 604 and gutter cleaning flow channel outlets 606 can be manufactured by any of a variety of suitable methods, such as by machining countersunk holes at precise angles. Each hole angle determines a restricted length, which must be equal in all holes for uniform flow. The countersunk holes provide a spread length so that the flow exits fully spread.

[0113] In some aspects, the flow of gaseous fluid (e.g., 0.5 bar of H2 generated by a gaseous fluid source) through (a) the nozzle flow distribution plenum 680, the nozzle flow expansion plenum 682, the plurality of nozzle flow channel outlets 604, and the gutter wash flow channel outlet 606, and (b) the perimeter flow distribution plenum 684, the perimeter flow expansion plenum 686, and the perimeter flow channel outlet 620 can be configured to generate an overall non-uniformity of gas flow (less than about 5%, less than about 3%, or less than about 1%) between a plurality of first gaseous fluid flows (e.g., output from the plurality of nozzle flow channel outlets 604 at about 15 to 50 standard liters per minute (slm)), a second gaseous fluid flow (e.g., output from the perimeter flow channel outlet 620 at about 50 to 130 slm), and a third gaseous fluid flow. In some aspects, the gaseous fluid flows can be configured to generate a total pressure drop of less than about 15 kilopascals (kPa), 10 kPa, or 5 kPa between the plurality of first gaseous fluid flows, the second gaseous fluid flow, and the third gaseous fluid flow. In some aspects, the gaseous fluid flows can be configured to generate a flow distribution of about 70% and about 30% for the plurality of first gaseous fluid flows and the second gaseous fluid flow, respectively. In some aspects, the gaseous fluid flows can be configured to generate a flow distribution of about 50% flowing upward (e.g., across the plasma-facing surface 602a) and 50% flowing toward the radiation collector CO for the third gaseous fluid flow. In other embodiments, any of a variety of other flow rates and relative flow rates can be used.

[0114] Example Process for Manufacturing a CFR Housing

[0115] Figure 7 An example method 700 is provided for manufacturing a CFR housing (e.g., CFR housing 502 or 602) configured to mitigate accumulation of fuel debris in an EUV radiation system, according to aspects of the present disclosure or portion(s) thereof. The operations described with reference to the example method 700 may be performed by or in accordance with any of the systems, devices, assemblies, techniques, or combinations thereof described herein, such as those described with reference to FIGs. 1-6.

[0116] At operation 702, the method may include forming a plurality of showerhead flow channel outlets (e.g., the plurality of showerhead flow channel outlets 604) configured to output a plurality of first gaseous fluid flows over a plurality of portions of a plasma-facing surface of a CFR housing (e.g., the plasma-facing surface 602a). In some aspects, forming the plurality of showerhead flow channel outlets may be accomplished using a suitable mechanical or other method and include forming the plurality of showerhead flow channel outlets according to any aspect or combination of aspects described with reference to FIG. 1-6.

[0117] At operation 704, the method may include forming a gutter wash flow channel outlet (e.g., gutter wash flow channel outlet 606) configured to output the second gaseous fluid flow above a fuel debris receiving surface of the CFR housing (e.g., fuel debris receiving surface 602b). In some aspects, forming the gutter wash flow channel outlet may be accomplished using a suitable mechanical or other method and may include forming the gutter wash flow channel outlet according to any or a combination of the aspects described with reference to FIG. 1 through FIG. 6.

[0118] At operation 706, the method may include forming a shield mounting structure configured to support a shield assembly (e.g., shield assembly 520). In some aspects, forming the shield mounting structure may be accomplished using suitable machinery or other methods and include forming the shield mounting structure according to any aspect or combination of aspects described with reference to FIG. 1-6.

[0119] At operation 708, the method may include forming a cooling flow channel (e.g., cooling flow channel 612) configured to convey a fluid configured to remove heat from at least a portion of the CFR housing during EUV radiation generation operation of the EUV radiation system. In some aspects, forming the cooling flow channel can be accomplished using suitable mechanical or other methods and include forming the cooling flow channel according to any aspect or combination of aspects described with reference to FIG. 1 through FIG. 6 .

[0120] At operation 710, the method may include forming a plurality of optical measurement ports (e.g., the plurality of optical measurement ports 616) configured to receive a plurality of optical measurement tubes. In some aspects, forming the plurality of optical measurement ports may be accomplished using suitable mechanical or other methods and may include forming the plurality of optical measurement ports according to any or a combination of aspects described with reference to FIG. 1 through FIG. 6 .

[0121] Optionally, the method can include forming a first gaseous fluid chamber (e.g., a sprinkler flow expansion plenum 682) configured to be fluidly coupled to a plurality of sprinkler flow channel outlets and a gutter wash flow channel outlet. Optionally, the method can also include forming a second gaseous fluid chamber (e.g., a sprinkler flow distribution plenum 680) configured to be fluidly coupled to the first gaseous fluid chamber. In some aspects, the gaseous fluid source can be configured to output a gaseous fluid (e.g., H2) that can be configured to flow (i) through the first gaseous fluid chamber, then (ii) through the second gaseous fluid chamber, and finally (iii) through the plurality of sprinkler flow channel outlets and the gutter wash flow channel outlet to generate an overall non-uniformity of gas flow between the plurality of first gaseous fluid flows and the second gaseous fluid flow of less than about 5%, less than about 3%, or less than about 1%.

[0122] Optionally, the method may include forming a weight-reducing cavity (e.g., Figure 5 The method may further include forming a plurality of calorimetric channels configured to support a plurality of calorimetric devices (e.g., thermocouple-based devices). The method may further include forming a plurality of collector rail mounting structures (e.g., plurality of collector rail mounting structures 540) configured to attach to a plurality of collector rails (e.g., plurality of collector rails 542). The method may further include forming a CFR housing of Al. The method may further include forming a coating of at least one material selected from the group consisting of TiN, Sn, or Ni.

[0123] Example EUV radiation source with CFR housing

[0124] In some aspects, the present disclosure provides an EUV radiation source (e.g., radiation source S0) including a laser source (e.g., laser system 401) configured to generate optical pulses (e.g., one or more laser beams 402) configured to irradiate a fuel material (e.g., one or more of fuel targets 403') at an irradiation location (e.g., plasma formation region 404), the irradiated fuel material at the irradiation location configured to generate a plasma (e.g., plasma 407) configured to emit EUV radiation.

[0125] The EUV radiation source may also include a fuel source (eg, fuel target generator 403) configured to deliver fuel material to the irradiation location.

[0126] The EUV radiation source may further include a CFR housing (e.g., CFR housing 502, 602). The CFR housing may include a plurality of showerhead flow channel outlets (e.g., showerhead flow channel outlets 604) configured to output a plurality of first gaseous fluid flows over portions of a plasma-facing surface of the CFR housing (e.g., plasma-facing surface 602a). The CFR housing may further include a gutter wash flow channel outlet (e.g., gutter wash flow channel outlet 606) configured to output a second gaseous fluid flow over a fuel debris receiving surface of the CFR housing (e.g., fuel debris receiving surface 602b). The CFR housing may further include a shroud mounting structure configured to support a shroud assembly (e.g., shroud assembly 520). The CFR housing may further include a cooling flow channel (e.g., cooling flow channel 612) configured to convey a liquid fluid configured to remove heat from at least a portion of the CFR housing during EUV radiation generating operation of the EUV radiation system. The CFR housing can also include a plurality of optical measurement ports (e.g., plurality of optical measurement ports 616) configured to receive a plurality of optical measurement tubes (e.g., plurality of optical measurement tubes 618). In some aspects, the CFR housing can also include a weight reduction cavity (e.g., weight reduction cavity 522) configured to reduce the overall mass of the CFR housing and modify the center of gravity of the CFR housing. In some aspects, the CFR housing can also include a plurality of collector rail mounting structures (e.g., plurality of collector rail mounting structures 540) configured to attach to a plurality of collector rails (e.g., plurality of collector rails 542).

[0127] In some aspects, the plurality of nozzle flow channel outlets can be configured to be fluidly coupled to a gaseous fluid chamber (e.g., nozzle flow distribution plenum 680, nozzle flow expansion plenum 682), which is configured to be fluidly coupled to a gaseous fluid source. In some aspects, the gutter cleaning flow channel is configured to be fluidly coupled to the gaseous fluid chamber. In some aspects, the EUV radiation source can include a third control signal configured to instruct the gaseous fluid source to control a third gaseous fluid flow through the gaseous fluid chamber. In some aspects, the third gaseous fluid flow through the gaseous fluid chamber can be configured to generate an overall non-uniformity of gaseous fluid flow between the plurality of first gaseous fluid flows and the second gaseous fluid flow of less than about 5%.

[0128] In some aspects, the plurality of sprinkler flow channel outlets, the gutter wash flow channel outlets, and the plurality of optical metering ports are disposed on a body (e.g., a single piece of material) of the collector flow ring housing. Figure 5A lightening cavity 522 is also formed in the body (e.g., a single piece of material). In some aspects, the collector flow ring housing can include aluminum (Al). In some aspects, the collector flow ring housing can include a coating of at least one material selected from the group consisting of titanium nitride (TiN), tin (Sn), or nickel (Ni).

[0129] The EUV radiation source may further include a controller (e.g., controller 411) configured to generate a first control signal configured to instruct the laser source to generate optical pulses. The controller may further be configured to generate a second control signal configured to instruct the fuel source to deliver fuel material. The controller may further be configured to generate a third control signal configured to instruct a gaseous fluid source (e.g., gas supply 524, 628) to control the output of a plurality of first gaseous fluid flows from a plurality of nozzle flow channel outlets. The third control signal may further be configured to instruct the gaseous fluid source to control the output of a second gaseous fluid flow from a gutter cleaning flow channel outlet. The controller may further be configured to generate a fourth control signal configured to instruct a liquid fluid source (e.g., cooling fluid supply 506) to control the delivery of liquid fluid in the cooling flow channel.

[0130] The EUV radiation source may further include a plurality of calorimetric devices (e.g., thermocouple-based devices) configured to generate a plurality of thermal measurement signals associated with the CFR housing and transmit the plurality of thermal measurement signals to the controller. The CFR housing may further include a plurality of calorimetric channels configured to support the plurality of calorimetric devices. The controller may further be configured to receive the plurality of thermal measurement signals from the plurality of calorimetric devices and generate a plurality of thermal measurement values ​​(e.g., temperature values, temperature gradients, heat fluxes, and other suitable values) associated with the CFR housing based on the plurality of received thermal measurement signals.

[0131] Although specific reference may be made herein to the use of lithographic apparatus in the manufacture of ICs, it will be appreciated that the lithographic apparatus described herein may have other applications, such as in the manufacture of integrated optical systems, guidance and detection patterns for magnetic domain memories, flat panel displays, LCDs, thin film heads, and the like. One skilled in the art will appreciate that in the context of such alternative applications, any use of the terms "wafer" or "die" herein may be considered synonymous with the more general terms "substrate" or "target portion", respectively. The substrate referred to herein may be processed, before or after exposure, in, for example, a tracking unit (a tool which typically applies a layer of resist to a substrate and develops the exposed resist), a metrology unit, and / or an inspection unit. Where applicable, the disclosure herein may be applied to such and other substrate processing tools. Furthermore, a substrate may be processed more than once, for example to create a multi-layer IC, so that the term substrate as used herein may also refer to a substrate which already contains multiple processed layers.

[0132] It is to be understood that the phraseology or terminology herein is for the purpose of description and not limitation, so that the phraseology or terminology of the present disclosure should be interpreted by those skilled in the relevant art based on the teachings herein.

[0133] As used herein, the term "substrate" describes a material onto which a layer of material is added. In some embodiments, the substrate itself can be patterned, and the material added on top of it can also be patterned, or can remain unpatterned.

[0134] The embodiments disclosed herein are illustrative of the embodiments of the present disclosure and are not limiting. Other suitable modifications and adaptations of the various conditions and parameters normally encountered in the art (which will be apparent to those skilled in the relevant art) are within the spirit and scope of the present disclosure.

[0135] While certain aspects of the present disclosure have been described above, it should be understood that the aspects may be practiced in ways other than as described. This description is not intended to limit the embodiments of the present disclosure.

[0136] It should be understood that the detailed description section, rather than the technical background, summary, and abstract sections, is intended to be used to interpret the claims. The summary and abstract sections may set forth one or more, but not all, exemplary embodiments contemplated by the inventors, and therefore are not intended to limit the present embodiments and the appended claims in any way.

[0137] Some aspects of the present disclosure are described above by means of functional building blocks that illustrate the implementation of specific functions and their relationships. For ease of description, the boundaries of these functional building blocks are arbitrarily defined in this article. As long as the specified functions and their relationships are properly performed, alternative boundaries can be defined.

[0138] The above description of specific embodiments will fully reveal the general nature of these aspects, and by applying the knowledge in the art, others can readily modify and / or adapt these specific aspects for various applications without undue experimentation and without departing from the general concepts of the present disclosure. Therefore, based on the teaching and guidance provided herein, such adaptations and modifications are intended to be within the meaning and range of equivalents of the disclosed aspects.

[0139] Implementations of the present disclosure may be further described using the following terms:

[0140] 1. A collector flow ring housing configured to mitigate accumulation of fuel debris in an extreme ultraviolet (EUV) radiation system, the collector flow ring housing comprising:

[0141] a plurality of showerhead flow channel outlets configured to: output a plurality of first gaseous fluid flows over a plurality of portions of a plasma-facing surface of the collector flow ring housing;

[0142] a gutter wash flow passage outlet configured to: output a second gaseous fluid flow over a fuel debris receiving surface of the collector flow ring housing;

[0143] a shroud mounting structure configured to support the shroud assembly;

[0144] a cooling flow channel configured to convey a fluid configured to remove heat from at least a portion of the collector flow ring housing during EUV radiation generating operation of the EUV radiation system; and

[0145] The plurality of optical measurement ports are configured to receive a plurality of optical measurement tubes.

[0146] 2. The collector flow ring housing of clause 1, wherein:

[0147] The plurality of showerhead flow channel outlets are configured to: fluidly couple to the gaseous fluid chamber;

[0148] The gutter cleaning flow channel is configured to: fluidly couple to the gaseous fluid chamber; and

[0149] The gaseous fluid chamber is configured to generate an overall non-uniformity of gaseous fluid flow between the plurality of first gaseous fluid flows and the second gaseous fluid flow of less than about 5%.

[0150] 3. The collector flow ring housing of clause 1, wherein the plurality of spray head flow channel outlets, the gutter wash flow channel outlets, and the plurality of optical metering ports are provided in a single piece of material forming the body of the collector flow ring housing.

[0151] 4. The collector flow ring housing according to clause 3, further comprising a lightening cavity formed in the body of the collector flow ring housing and configured to:

[0152] Reducing the overall mass of the collector flow ring housing; and

[0153] Modify the center of gravity of the collector flow ring shell.

[0154] 5. The collector flow ring housing of clause 1, further comprising a plurality of calorimetric channels, the plurality of calorimetric channels configured to support a plurality of calorimetric devices.

[0155] 6. The collector flow ring housing of clause 1, further comprising a plurality of collector rail mounting structures configured to attach to the plurality of collector rails.

[0156] 7. The collector flow ring housing of clause 1, wherein the collector flow ring housing comprises aluminum (Al).

[0157] 8. The collector flow ring housing of clause 1, further comprising a coating of at least one material selected from the group consisting of: titanium nitride (TiN), tin (Sn), and nickel (Ni).

[0158] 9. An extreme ultraviolet (EUV) radiation source comprising:

[0159] a laser source configured to generate optical pulses configured to irradiate a fuel material at an irradiation location, the irradiated fuel material at the irradiation location configured to generate a plasma that emits EUV radiation;

[0160] a fuel source configured to deliver fuel material to the irradiation location;

[0161] Collector flow ring housing, comprising:

[0162] a plurality of showerhead flow channel outlets configured to output a plurality of first gaseous fluid flows over a plurality of portions of the plasma-facing surface of the collector flow ring housing,

[0163] a gutter wash flow passage outlet configured to output a second gaseous fluid flow over a fuel debris receiving surface of the collector flow ring housing,

[0164] a shroud mounting structure configured to support the shroud assembly, and

[0165] A cooling flow channel is configured to convey a liquid fluid configured to remove heat from at least a portion of the collector flow ring housing during EUV radiation generating operation of the EUV radiation system.

[0166] 10. The EUV radiation source according to clause 9, further comprising:

[0167] a plurality of optical measurement ports configured to receive a plurality of optical measurement tubes; and

[0168] The controller is configured as:

[0169] generating a first control signal configured to instruct the laser source to generate an optical pulse,

[0170] generating a second control signal configured to instruct the fuel source to deliver the fuel material,

[0171] generating a third control signal configured to instruct the gaseous fluid source to control output of a plurality of first gaseous fluid flows from a plurality of sprinkler flow channel outlets, wherein the third control signal is further configured to instruct the gaseous fluid source to control output of a second gaseous fluid flow from a gutter cleaning flow channel outlet, and

[0172] A fourth control signal is generated, the fourth control signal being configured to instruct the liquid fluid source to control delivery of the liquid fluid in the cooling flow channel.

[0173] 11. An EUV radiation source according to clause 10, wherein:

[0174] a plurality of showerhead flow channel outlets configured to be fluidly coupled to a gaseous fluid chamber, the gaseous fluid chamber configured to be fluidly coupled to a gaseous fluid source;

[0175] The gutter cleaning flow channel is configured to be fluidly coupled to the gaseous fluid chamber;

[0176] a third control signal configured to instruct the gaseous fluid source to control flow of a third gaseous fluid through the gaseous fluid chamber;

[0177] The third gaseous fluid flow through the gaseous fluid chamber is configured to generate an overall non-uniformity of gaseous fluid flow between the plurality of first gaseous fluid flows and the second gaseous fluid flow of less than about 5%.

[0178] 12. The EUV radiation source of clause 10, wherein the plurality of showerhead flow channel outlets, the gutter cleaning flow channel outlets and the plurality of optical metrology ports are provided in a single piece of material forming a body of the collector flow ring housing.

[0179] 13. The EUV radiation source according to clause 12, wherein the collector flow ring housing further comprises a lightening cavity formed in the body of the collector flow ring housing and configured to:

[0180] Reducing the overall mass of the collector flow ring housing; and

[0181] Modify the center of gravity of the collector flow ring shell.

[0182] 14. The EUV radiation source of clause 10, further comprising a plurality of calorimetric devices configured to generate a plurality of thermal measurement signals associated with the collector flow ring housing and transmit the plurality of thermal measurement signals to the controller.

[0183] The collector flow ring housing further comprises a plurality of calorimetric channels, the plurality of calorimetric channels being configured to support a plurality of calorimetric devices, and

[0184] The controller is further configured to receive a plurality of thermal measurement signals from the plurality of thermal measurement devices, and generate a plurality of thermal measurement values ​​associated with the collector flow ring housing based on the received plurality of thermal measurement signals.

[0185] 15. The EUV radiation source of clause 10, wherein the collector flow ring housing further comprises a plurality of collector rail mounting structures configured to attach to the plurality of collector rails.

[0186] 16. A method for manufacturing a collector flow ring housing configured to mitigate accumulation of fuel debris in an extreme ultraviolet (EUV) radiation system, the method comprising:

[0187] forming a plurality of showerhead flow channel outlets in a body of the collector flow ring housing, the plurality of showerhead flow channel outlets being configured to: output a plurality of first gaseous fluid flows over a plurality of portions of a plasma-facing surface of the collector flow ring housing;

[0188] forming a gutter purge flow passage outlet in a body of the collector flow ring housing, the gutter purge flow passage outlet configured to: output a second gaseous fluid flow over a fuel debris receiving surface of the collector flow ring housing;

[0189] forming a shroud mounting structure configured to support the shroud assembly;

[0190] forming a cooling flow channel configured to convey a fluid configured to remove heat from at least a portion of the collector flow ring housing during EUV radiation generating operation of the EUV radiation system; and

[0191] A plurality of optical metering ports are formed in the body of the collector flow ring housing, the plurality of optical metering ports being configured to receive the plurality of optical metering tubes.

[0192] 17. The method according to clause 16, further comprising:

[0193] providing a first gaseous fluid chamber configured to be fluidly coupled to a plurality of showerhead flow channel outlets and a gutter wash flow channel outlet; and

[0194] A second gaseous fluid chamber is provided, the second gaseous fluid chamber being configured to be fluidly coupled to the first gaseous fluid chamber, wherein

[0195] The first and second gaseous fluid chambers are configured to generate an overall non-uniformity of gas flow of less than about 5% between the plurality of first and second gaseous fluid flows.

[0196] 18. The method of clause 16, further comprising: forming a lightening cavity in the body of the collector flow ring housing, the lightening cavity being configured to:

[0197] Reducing the overall mass of the collector flow ring housing; and

[0198] Modify the center of gravity of the collector flow ring shell.

[0199] 19. The method of clause 16, further comprising: forming a plurality of calorimetry channels, the plurality of calorimetry channels configured to support a plurality of calorimetry devices.

[0200] 20. The method of clause 16, further comprising forming a plurality of collector rail mounting structures, the collector rail mounting structures configured to attach to the plurality of collector rails, and wherein the collector flow ring housing is formed of aluminum (Al).

[0201] The breadth and scope of the present disclosure should not be limited by any of the above-described exemplary aspects or embodiments, but should be defined only in accordance with the following claims and their equivalents.

Claims

1. A modular apparatus positioned adjacent a collector mirror in a radiation source container, the modular apparatus comprising: a plurality of first flow channel outlets configured to output a plurality of first gaseous fluid flows directed inwardly toward an interior region of the radiation source container; a shroud mounting structure configured for coupling with the shroud assembly; a plurality of measurement ports configured to couple with optical measurement devices and / or thermal measurement devices; and Cooling fluid channel assembly.

2. The modular device according to claim 1, further comprising: At least one second flow channel outlet is configured to output a second gaseous fluid flow different from the plurality of first gaseous fluid flows, wherein the plurality of first flow channel outlets are located between the at least one second flow channel outlet and the collector mirror.

3. The modular device according to claim 2, further comprising: A first flow expansion plenum is fluidly coupled to a gas supply and the plurality of first flow channel outlets, wherein the first flow expansion plenum is configured to provide a pressure reservoir for the plurality of first gaseous fluid flows.

4. The modular device of claim 1 , further comprising: At least one third flow channel outlet is configured to output a third gaseous fluid flow different from the plurality of first gaseous fluid flows, wherein the at least one third flow channel outlet is located between the plurality of first flow channel outlets and the collector mirror.

5. The modular device according to claim 4, further comprising: A second flow expansion plenum is fluidly coupled to the at least one third flow channel outlet, wherein the second flow expansion plenum is sealed by a plate located at a bottom of the modular device.

6. The modular device of claim 1 , further comprising: A placeholder is provided for coupling to an insert device, wherein the placeholder is aligned with the shield mounting structure.

7. A radiation source comprising: collector reflector; as well as a modular apparatus positioned adjacent to the collector mirror, wherein the modular apparatus comprises: a plurality of first flow channel outlets configured to output a plurality of first gaseous fluid flows directed inwardly toward an interior region of the radiation source; a plurality of second flow channel outlets configured to output a plurality of second gaseous fluid flows directed inwardly toward the interior region of the radiation source; a shroud mounting structure configured for coupling with the shroud assembly; at least one optical measurement port configured to couple with a measurement device; and A plurality of mounting structures are configured for coupling to the collector mirror.

8. The radiation source of claim 7, wherein the modular apparatus further comprises: At least one third flow channel outlet is configured to output a third gaseous fluid flow different from the plurality of first gaseous fluid flows and the plurality of second gaseous fluid flows, wherein the third gaseous fluid flow is directed inwardly toward the interior region of the radiation source.

9. The radiation source of claim 8, wherein the modular apparatus further comprises: a first gaseous chamber fluidly coupled to the plurality of first flow channel outlets and the at least one third flow channel outlet; A second gaseous chamber is fluidly coupled to the first gaseous chamber and a gas supply.

10. The radiation source of claim 7, wherein the modular apparatus further comprises: a peripheral flow ring having mesh rings distributed along an inner surface of the modular device; as well as A peripheral skin panel is located between the peripheral flow ring and the plurality of mounting structures, wherein the combination of the peripheral flow ring and the peripheral skin panel forms the plurality of second flow channel outlets.

11. The radiation source of claim 7, wherein the plurality of second gaseous fluid flows comprises a first sub-flow directed in a first direction, and a second sub-flow directed in a second direction different from the first direction, the second direction being directed toward the collector mirror.

12. A method for generating extreme ultraviolet (EUV) radiation, comprising: irradiating the target material to generate plasma at a plasma formation region within the container, wherein debris is formed around the plasma formation region; emitting EUV radiation from the plasma toward a collector mirror; Outputting a plurality of first gaseous fluid flows from the plurality of first flow channel outlets, wherein the first gaseous fluid flows are directed inwardly toward the plasma formation region; outputting at least one second gaseous fluid flow from the at least one second flow channel outlet above the debris receiving surface; outputting a plurality of third gaseous fluid flows from a plurality of third flow channel outlets, wherein the third gaseous fluid flows are directed inwardly toward the plasma formation region and the collector reflector; as well as A shield assembly is installed to protect the target material, wherein the plurality of first flow channel outlets, the at least one second flow channel outlet, the plurality of third flow channel outlets, and the shield assembly are integrated into a modular device positioned adjacent to the collector mirror.

13. The method according to claim 12, further comprising: A liquid fluid is flowed through a plurality of cooling flow channels to remove heat from at least a portion of the modular device, wherein the cooling flow channels are integrated into the modular device.

14. The method according to claim 12, further comprising: A uniform fluid flow outlet is generated from a first gaseous chamber shared by the plurality of first flow channel outlets and the at least one second flow channel outlet.

15. The method according to claim 12, further comprising: An overall non-uniformity of gaseous fluid flow of less than about 5% is generated between the plurality of first gaseous fluid flows and the at least one second gaseous fluid flow.

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