Transfer cartridge for patterning device

Abstract

A system includes a first container and a second container. The first container receives the patterning device and maintains a predetermined environment within the first container. The second container receives the first container and maintains a vacuum within the second container. The second container includes a flange, a first end, and a second end. The flange is external to the second container. The second container may be gripped and transported via the flange. The first end includes a vacuum valve and a purge valve. A vacuum valve facilitates removal of gas from the second container. A purge valve facilitates introduction of gas into the second container. The vacuum valve and the purge valve are connected with a first external vacuum environment. The second end is opposite the first end, and the second end has an opening. The opening allows the first container to be removed from the second container.

Description

[0001] Cross - reference to related applications

[0002] This application claims the priority of U.S. Application No. 63 / 435,180, filed on December 23, 2022, which is incorporated herein by reference in its entirety. Technical field

[0003] The present disclosure relates to a transfer pod for a patterning device, such as an external transfer pod for handling a mask stored in an internal transfer pod in a lithography apparatus, and a system. Background art

[0004] A lithography apparatus is a machine that applies a desired pattern onto a substrate (usually onto a target portion of the substrate). A lithography apparatus can be used, for example, in the manufacture of integrated circuits (ICs). In that case, a patterning device (the patterning device may alternatively be referred to as a mask or a reticle) can be used to generate a circuit pattern to be formed on an individual layer of the IC. Such a pattern can be transferred onto a target portion (e.g., a portion including dies, one die, or several dies) on the substrate (e.g., a silicon wafer). The transfer of the pattern is typically via imaging onto a layer of radiation - sensitive material (resist) provided on the substrate. Usually, a single substrate will contain a network of adjacent target portions that are successively patterned. Known lithography apparatuses include so - called steppers, in which each target portion is irradiated by exposing the entire pattern at once to the target portion; and so - called scanners, in which each target portion is irradiated by scanning the radiation beam in a given direction (the "scanning" direction) while synchronously scanning the target portion parallel or antiparallel to the scanning direction. The pattern can also be transferred from the patterning device to the substrate by printing the pattern onto the substrate.

[0005] During a lithography operation, different processing steps may require different layers to be successively formed on the substrate. Therefore, it may be necessary to position the substrate with high accuracy relative to an existing pattern formed on the substrate. Usually, alignment marks are placed on the substrate to be aligned and are positioned with reference to a second object. The lithography apparatus can use an alignment device to detect the position of the alignment marks and use the alignment marks to align the substrate to ensure accurate exposure from the mask. The misalignment between alignment marks at two different layers is measured as an overlay error.

[0006] To monitor the lithography process, parameters of the patterned substrate are measured. For example, the parameters can include overlay errors between successive layers formed in or on the patterned substrate and critical linewidths of the developed photoresist. The measurement can be performed on product substrates and / or dedicated metrology targets. There are various techniques for measuring the microstructures formed during the lithography process, including using scanning electron microscopes and various dedicated tools. A fast and non-invasive dedicated inspection tool is a scatterometer, in which a radiation beam is directed onto a target on the surface of the substrate and the properties of the scattered or reflected beam are measured. By comparing the properties of the beam before and after the beam is reflected or scattered by the substrate, the properties of the substrate can be determined. For example, this can be achieved by comparing the reflected beam with data stored in a library of known measurement results associated with known substrate properties. A spectroscopic scatterometer directs a broadband radiation beam onto the substrate and measures the spectrum (intensity as a function of wavelength) of the radiation scattered into a specific narrow angular range. In contrast, an angularly resolved scatterometer uses a monochromatic radiation beam and measures the intensity of the scattered radiation as a function of angle.

[0007] Such an optical scatterometer can be used to measure parameters such as the critical dimension of the developed photoresist or the overlay error (OV) between two layers formed in or on the patterned substrate. By comparing the properties of the illumination beam before and after the illumination beam is reflected or scattered by the substrate, the properties of the substrate can be determined.

[0008] A lithographic apparatus can include a supply chain and transfer mechanism for a mask. The mask can be moved from a non-vacuum environment to a vacuum environment. For example, the mask can be stored in a cassette and moved from a customer (non-vacuum environment) to a lithographic apparatus (vacuum environment). The cassette can be a specialized enclosure configured to fixedly and securely hold the mask in a controlled environment. Some conventional extreme ultraviolet (EUV) external cassettes may not be able to maintain a vacuum. This can lead to additional steps when moving a mask placed in an internal cassette (such as an EUV internal cassette (EIP) from a customer) into the vacuum environment of the lithographic apparatus. For example, the external cassette may not meet the cleanliness requirements of an automated handling machine. In addition, the contamination risk and cost of the EIP and the mask may increase due to additional equipment used to transfer the cassette from a non-vacuum environment to a vacuum environment. Contamination (such as particles during the exposure process) can cause wafer lead problems. SUMMARY OF THE INVENTION

[0009] Accordingly, there is a desire to improve performance and cleanliness. For example, there is a desire to provide an external cassette that maintains a vacuum as discussed in the embodiments herein.

[0010] In some embodiments, a system includes a first container and a second container. The first container receives a patterning device and maintains a predetermined environment within the first container. The second container receives the first container and maintains a vacuum within the second container. The second container includes a flange, a first end, and a second end. The flange is located outside the second container. The second container can be clamped and transported via the flange. The first end includes a vacuum valve and a purge valve. The vacuum valve facilitates removing gas from the second container. The purge valve facilitates introducing gas into the second container. The vacuum valve and the purge valve are connected to a first external vacuum environment. The second end is opposite the first end and has an opening. The opening allows the first container to be removed from the second container.

[0011] In some embodiments, a method includes receiving a patterning device in a first container, maintaining the first container in a predetermined environment, receiving the first container in a second container, maintaining the second container at a vacuum level, transporting the second container via a flange located outside the second container, removing gas from the second container through a vacuum valve connected to a first external vacuum environment, introducing gas into the second container through a purge valve connected to the first external vacuum environment; and removing the first container from the second container through the opening.

[0012] In some embodiments, an external transfer cassette includes a housing, a flange, an end, and a channel door. The flange is located outside the housing. The external transfer cassette is clamped and transported via the flange. The first end has an opening. The opening is configured to allow removal of an internal transfer cassette stored in the external transfer cassette and is connected to an external vacuum environment. A channel seals the opening.

[0013] Other features of the present disclosure, as well as the structure and operation of various embodiments, 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 embodiments described herein. These embodiments are presented herein for illustrative purposes only. Based on the teachings contained herein, additional embodiments will be apparent to those skilled in the relevant art(s). BRIEF DESCRIPTION OF THE DRAWINGS

[0014] The accompanying drawings, which are incorporated herein and form a part of the specification, illustrate the present disclosure together with the description, and also serve to explain the principles of the present disclosure and enable those skilled in the relevant art(s) to practice and use the embodiments described herein.

[0015] Figure 1A A schematic diagram of a reflective lithography apparatus according to some embodiments is shown.

[0016] Figure 1B A schematic diagram of a transmissive lithography apparatus according to some embodiments is shown.

[0017] Figure 2 Shows a more detailed schematic diagram of a reflective lithography apparatus according to some embodiments.

[0018] Figure 3 Shows a schematic diagram of a lithography unit according to some embodiments.

[0019] Figure 4 Shows a schematic diagram of a processing system according to some embodiments.

[0020] Figure 5A and Figure 5B Shows a schematic diagram of an external transfer cassette according to some embodiments.

[0021] Figure 6 Shows a schematic diagram of an external transfer cassette with a detachable channel door according to some embodiments.

[0022] Figure 7A Shows a schematic diagram of an external transfer cassette with a rotating door according to some embodiments.

[0023] Figure 7B Shows according to some embodiments Figure 7A Cross-sectional schematic diagram of an external transfer cassette.

[0024] Figure 8A Shows a schematic diagram of an external transfer cassette with a rotating door according to some embodiments.

[0025] Figure 8B Shows according to some embodiments Figure 8A Schematic diagram of an external transfer cassette, where the channel door is in the raised position.

[0026] Figure 8C Shows according to some embodiments Figure 8A and Figure 8B Cross-sectional schematic diagram of the external transfer cassette in.

[0027] Figure 9 Shows a schematic diagram of an external transfer cassette according to some embodiments.

[0028] Figure 10 Shows a schematic diagram of a processing system according to some embodiments.

[0029] Figure 11 Is a flowchart of a method for processing an internal transfer cassette according to some embodiments.

[0030] The features of the present disclosure will become more apparent from the following detailed description taken in conjunction with the accompanying drawings, in which like reference numerals always identify corresponding elements. In the drawings, like reference numerals generally denote the same, functionally similar, and / or structurally similar elements. Additionally, the (multiple) leftmost digits of a reference numeral generally identify the drawing in which the reference numeral first appears. Unless otherwise noted, the drawings provided throughout the present disclosure should not be construed as being drawn to scale. Detailed Description

[0031] This specification discloses one or more embodiments incorporating features of the present disclosure. The disclosed embodiments are provided as examples. The scope of the present disclosure is not limited to the disclosed embodiments. The claimed features are defined by the appended claims.

[0032] The described embodiments and references in the specification to "one embodiment", "an embodiment", "example embodiment", etc., indicate that the described embodiments may include a particular feature, structure, or characteristic, but each embodiment may not necessarily include the particular feature, structure, or characteristic. Moreover, these phrases or terms do not necessarily refer to the same embodiment. Additionally, when a particular feature, structure, or characteristic is described in connection with an embodiment, it should be understood that implementing such feature, structure, or characteristic in connection with other embodiments is within the knowledge of those skilled in the art, whether or not such other aspects are explicitly described.

[0033] For ease of description, spatial relative terms such as "under", "below", "beneath", "over", "above", "on top" and the like may be used herein to describe the relationship of one element or feature in the drawings to another element or feature. Spatial relative terms are intended to encompass different orientations of the device or apparatus in use or operation in addition to the orientation depicted in the drawings. The device may be otherwise oriented (rotated 90 degrees or in other orientations), and the spatial relative descriptors used herein may be interpreted accordingly.

[0034] As used herein, the term "about" refers to a given value that may vary based on a particular technology. Based on a particular technology, the term "about" may mean a given value that varies within, for example, 10% to 30% (e.g., ±10%, ±20%, or ±30%) of the value.

[0035] Embodiments of the present disclosure may be implemented in hardware, firmware, software, or any combination thereof. Embodiments of the present disclosure may also be implemented as instructions stored on a machine-readable medium, which can be read and executed by one or more processors. The machine-readable medium may include any mechanism for storing or transmitting information in a form readable by a machine (e.g., a computing device). For example, the machine-readable medium may include read-only memory (ROM); random access memory (RAM); magnetic disk storage media; optical storage media; flash memory devices; electrical, optical, acoustic, or other forms of propagated signals (e.g., carrier waves, infrared signals, digital signals, etc.), and so on. In addition, firmware, software, routines, and / or instructions may be described herein as performing particular actions. However, it should be understood that these descriptions are for convenience only, and these actions are actually generated from a computing device, processor, controller, or other device that executes the firmware, software, routines, instructions, etc.

[0036] However, before describing these embodiments in more detail, it is instructive to present an example environment in which the embodiments of the present disclosure may be implemented.

[0037] Exemplary lithography system

[0038] Figure 1A and Figure 1B Schematic diagrams of a lithographic apparatus 100 and a lithographic apparatus 100' in which embodiments of the present disclosure may be implemented are shown respectively. The lithographic apparatus 100 and the lithographic apparatus 100' each include the following: an illumination system (illuminator) IL, which is configured to condition a radiation beam B (e.g., deep ultraviolet radiation or extreme ultraviolet radiation); a support structure (e.g., a mask table) MT, which is configured to support a patterning device (e.g., a mask, a reticle, or a dynamic patterning device) MA and is connected to a first positioner PM configured to accurately position the patterning device MA; and a substrate table (e.g., a wafer table) WT, which is configured to hold a substrate (e.g., a wafer coated with resist) W and is connected to a second positioner PW configured to accurately position the substrate W. The lithographic apparatus 100 and the lithographic apparatus 100' also have a projection system PS, which is configured to project the pattern imparted to the radiation beam B by the patterning device MA onto a target portion C (e.g., including one or more dies) of the substrate W. In the lithographic apparatus 100, the patterning device MA and the projection system PS are reflective. In the lithographic apparatus 100', the patterning device MA and the projection system PS are transmissive.

[0039] 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.

[0040] 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 may use mechanical, vacuum, electrostatic, or other clamping techniques to hold the patterning device MA. The support structure MT may be, for example, a frame or a table, which may be fixed or movable (if required). By using sensors, the support structure MT can ensure that the patterning device MA is, for example, in a desired position relative to the projection system PS.

[0041] The term "patterning device" MA should be interpreted broadly to mean any device that can be used to impart a pattern to the radiation beam B in a cross-section of the 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 particular functional layer in a device that is to be formed in the target portion C to form an integrated circuit.

[0042] The terms "inspection device", "metrology system", etc. may be used herein to refer to, for example, a device or system for measuring properties of structures (such as overlay error, critical dimension parameters) or a device or system for inspecting the alignment of wafers in a lithographic apparatus (such as an alignment device).

[0043] The patterning device MA may be transmissive (as in the Figure 1B lithographic apparatus 100') or reflective (as in the Figure 1A lithographic apparatus 100). Examples of the patterning device MA include a reticle, a mask, a programmable mirror array, or a programmable LCD panel. Masks are well known in lithography and include mask types such as binary, alternating phase-shift, or attenuated phase-shift, as well as various hybrid mask types. An example of a programmable mirror array uses a matrix arrangement of small mirrors, each of which can be tilted individually so as to reflect an incident radiation beam in a different direction. The tilted mirrors impart a pattern in the radiation beam B that is reflected by the matrix of small mirrors.

[0044] The term "projection system" PS can cover any type of projection system suitable for the exposure radiation used or for other factors, such as the use of an immersion liquid on the substrate W or the use of a vacuum, including refractive, reflective, catadioptric, magnetic, electromagnetic, and electrostatic optical systems, or any combination thereof. Since other gases may absorb too much radiation or electrons, a vacuum environment can be used for EUV or electron beam radiation. Thus, by means of a vacuum wall and a vacuum pump, a vacuum environment can be set up for the entire beam path.

[0045] The lithographic apparatus 100 and / or the lithographic apparatus 100' can be of the type having two (dual-platform) or more substrate tables WT (and / or two or more mask tables). In such a "multi-platform" machine, additional substrate tables WT can be used in parallel, or one or more other substrate tables WT can be used for exposure while preparatory steps are carried out on one or more of the tables. In some cases, the additional table can be something other than a substrate table WT.

[0046] The lithographic apparatus can also be of the type in which at least a portion of the substrate is covered by a liquid having a relatively high refractive index (e.g., water) in order to fill the space between the projection system and the substrate. The immersion liquid can also be applied to other spaces in the lithographic apparatus, such as the space between the mask and the projection system. Immersion techniques for increasing the numerical aperture of the projection system are well known in the art. The term "immersion" as used herein does not mean that a structure such as a substrate must be immersed in a liquid, but only means that the liquid is located between the projection system and the substrate during exposure.

[0047] Reference Figure 1A and Figure 1B , the illuminator IL receives a radiation beam from the radiation source SO. For example, when the source SO is an excimer laser, the source SO and the lithographic apparatus 100, 100' can be separate physical entities. In such a case, the source SO is not considered to form part of the lithographic apparatus 100 or 100', and the radiation beam B is transmitted from the source SO to the illuminator IL by means of a beam delivery system BD ( Figure 1B in) including, for example, suitable directing mirrors and / or beam expanders. In other cases, for example, when the source SO is a mercury lamp, the source SO can be an integral part of the lithographic apparatus 100, 100'. The source SO and the illuminator IL and the beam delivery system BD (if required) can be referred to as the radiation system.

[0048] The illuminator IL can include an adjuster AD for adjusting the angular intensity distribution of the radiation beam ( Figure 1BIn the (middle). Generally, at least the outer radial range and / or the inner radial range of the intensity distribution in the pupil plane of the illuminator can be adjusted (commonly referred to as "σ - outer" and "σ - inner" respectively). Additionally, the illuminator IL can include various other components ( Figure 1B Including), such as the integrator IN and the condenser CO. The illuminator IL can be used to adjust the radiation beam B to have a desired uniformity and intensity distribution in its cross - section.

[0049] Reference Figure 1A , the 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 (e.g., a mask) MA. After being reflected from the patterning device (e.g., a mask) MA, the radiation beam B passes through the projection system PS, which focuses the radiation beam B onto a target portion C of the substrate W. By means of a second positioner PW and a position sensor IF2 (e.g., an interferometric device, a linear encoder, or a capacitive sensor), the substrate table WT can be accurately moved (e.g., to position different target portions C in the path of the radiation beam B). Similarly, a first positioner PM and another position sensor IF1 can be used to accurately position the patterning device (e.g., a mask) MA relative to the path of the radiation beam B. Mask alignment marks M1, M2 and substrate alignment marks P1, P2 can be used to align the patterning device (e.g., a mask) MA and the substrate W.

[0050] Reference Figure 1B , the 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. After passing through the mask 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 conjugate PPU with respect to the pupil IPU of the illumination system. Multiple portions of the radiation emanate from the intensity distribution at the illumination system pupil IPU, pass through the mask pattern without being affected by diffraction at the mask pattern, and produce an image of the intensity distribution at the illumination system pupil IPU.

[0051] The projection system PS projects an image of the mask pattern MP onto the photoresist layer coated on the substrate W, wherein the image is formed by diffracted beams generated from the mask pattern MP by radiation from an intensity distribution. For example, the mask pattern MP may include an array of lines and spaces. Radiation diffraction at the array other than the zero-order diffraction generates a deflected diffracted beam having a direction change in a direction perpendicular to the lines. The undiffracted beam (i.e., the so-called zero-order diffracted beam) passes through the pattern without any change in the propagation direction. The zero-order diffracted beam passes through the upper lens or upper lens group of the projection system PS located upstream of the pupil conjugate PPU of the projection system PS to reach the pupil conjugate PPU. The portion of the intensity distribution in the plane of the pupil conjugate PPU and associated with the zero-order diffracted beam is an image of the intensity distribution in the illumination system pupil IPU of the illumination system IL. The aperture device PD is provided, for example, at or substantially at the plane including the pupil conjugate PPU of the projection system PS.

[0052] The projection system PS is arranged to capture not only the zero-order diffracted beam but also the first-order diffracted beam, or the first-order and higher-order diffracted beams (not shown) by using a lens or lens group L. In some embodiments, dipole illumination for imaging line patterns extending in a direction perpendicular to the lines can be used to utilize the resolution enhancement effect of dipole illumination. For example, at the level of the wafer W, the first-order diffracted beam interferes with the corresponding zero-order diffracted beam to produce an image of the line pattern MP with the highest possible resolution and process window (i.e., the available depth of focus and the allowable exposure dose deviation). In some embodiments, astigmatism can be reduced by providing radiation poles (not shown) in opposite quadrants of the illumination system pupil IPU. Additionally, in some embodiments, astigmatism can be reduced by blocking the zero-order beam in the pupil conjugate PPU of the projection system associated with the radiation poles in the opposite quadrants. This is described in more detail in US 7,511,799 B2, issued on March 31, 2009, the entire content of which is incorporated herein by reference in its entirety.

[0053] By means of a second locator PW and a position sensor IFD (e.g., an interferometric device, a linear encoder, or a capacitive sensor), the substrate stage WT can be accurately moved (e.g., to position different target portions C in the path of the radiation beam B). Similarly, a first locator PM and another position sensor ( Figure 1B not shown in the figure) can be used to accurately position the mask MA relative to the path of the radiation beam B (e.g., after mechanical retrieval from a mask library or during scanning).

[0054] Generally, the movement of the mask table MT can be achieved by means of a long-stroke module (coarse positioning) and a short-stroke module (fine positioning) that form part of the first locator PM. Similarly, the movement of the substrate table WT can be achieved using a long-stroke module and a short-stroke module that form part of the second locator PW. In the case of a stepper (as opposed to a scanner), the mask table MT can be connected only to the short-stroke actuator or can be fixed. Mask alignment marks M1, M2 and substrate alignment marks P1, P2 can be used to align the mask MA with the substrate W. Although the substrate alignment marks (as illustrated) occupy dedicated target portions, these marks can be located in the space between the target portions (referred to as scribe alignment marks). Similarly, in the case where more than one die is provided on the mask MA, the mask alignment marks can be located between the dies.

[0055] The mask table MT and the patterning device MA can be in a vacuum chamber V, in which a vacuum in-chamber robot IVR can be used to move the patterning device (such as a mask) into and out of the vacuum chamber. Optionally, when the mask table MT and the patterning device MA are outside the vacuum chamber, a vacuum out-chamber robot similar to the vacuum in-chamber robot IVR can be used to perform various transport operations. Both the vacuum in-chamber robot and the vacuum out-chamber robot need to be calibrated to smoothly transfer any payload (e.g., a mask) to the fixed motion brackets at the transfer station.

[0056] The lithographic apparatuses 100 and 100’ can be used in at least one of the following modes:

[0057] 1. In the step mode, when the entire pattern imparted to the radiation beam B is projected onto the target portion C at once (i.e., single static exposure), the support structure (e.g., the mask table) MT and the substrate table WT are kept substantially stationary. Then the substrate table WT is shifted in the X direction and / or the Y direction so that different target portions C can be exposed.

[0058] 2. In the scan mode, when the pattern imparted to the radiation beam B is projected onto the target portion C (i.e., single dynamic exposure), the support structure (e.g., the mask table) MT and the substrate table WT are scanned synchronously. The speed and direction of the substrate table WT relative to the support structure (e.g., the mask table) MT can be determined by the magnification (reduction ratio) and image inversion characteristics of the projection system PS.

[0059] 3. In another mode, when projecting the pattern imparted to the radiation beam B onto the target portion C, the support structure (e.g., the mask table) MT is kept substantially stationary, thus maintaining the programmable patterning device, and the substrate table WT is moved or scanned. A pulsed radiation source SO can be used, and the programmable patterning device is updated as required after each movement of the substrate table WT or between successive radiation pulses during the scan. This operating mode can be readily applied to maskless lithography using a programmable patterning device such as a programmable mirror array.

[0060] Combinations and / or variants of the described usage modes or completely different usage modes can also be employed.

[0061] In other embodiments, the lithographic apparatus 100 includes an extreme ultraviolet (EUV) source configured to generate an EUV radiation beam for EUV lithography. Generally, the EUV source is configured in a radiation system, and the corresponding illumination system is configured to condition the EUV radiation beam of the EUV source.

[0062] Figure 2 The lithographic apparatus 100 is shown in more detail and includes a source collector apparatus SO, an illumination system IL, and a projection system PS. The source collector apparatus SO is constructed and arranged such that a vacuum environment can be maintained in the enclosure structure 220 of the source collector apparatus SO. The EUV radiation emitting plasma 210 can be formed by a discharge generated plasma source. The EUV radiation can be generated by a gas or vapor (e.g., Xe gas, Li vapor, or Sn vapor), where a very hot plasma 210 is generated to emit radiation in the EUV range of the electromagnetic spectrum. A very hot plasma 210 is generated, for example, by a discharge, which results in at least a partially ionized plasma. A partial pressure of, for example, 10 Pa of Xe, Li, Sn vapor or any other suitable gas or vapor may be required to effectively generate the radiation. In some embodiments, a plasma of excited tin (Sn) is provided to generate EUV radiation.

[0063] The radiation emitted by the hot plasma 210 enters the collector chamber 212 from the source chamber 11 via an optional gas barrier or contaminant trap 230 (also referred to in some cases as a contaminant barrier or fin trap), which is positioned in or behind an opening in the source chamber 211. The contaminant trap 230 can include a channel structure. The contaminant trap 230 can also include a gas barrier or a combination of a gas barrier and a channel structure. Herein, the contaminant trap or contaminant barrier 230 is additionally indicated as including at least a channel structure.

[0064] The collector chamber 212 may include a radiation collector CO, 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 out by the grating spectral filter 240 to be focused at the virtual source point INTF. The virtual source point INTF is commonly referred to as the intermediate focus, and the source collector device is arranged such that the intermediate focus INTF is positioned at or near the opening 219 in the enclosure structure 220. The virtual source point INTF is an image of the radiation-emitting plasma 210. The grating spectral filter 240 is particularly used to suppress infrared (IR) radiation.

[0065] Subsequently, the radiation passes through the illumination system IL, which may include a faceted field mirror device 222 and a faceted pupil mirror device 224. The faceted field mirror device 222 and the faceted pupil mirror device 224 are arranged to provide a desired angular distribution of the radiation beam 221 at the patterning device MA and a desired uniformity of the radiation intensity at the patterning device MA. When the radiation beam 221 is reflected at the patterning device MA held by the support structure MT, a patterned beam 226 is formed, and the patterned beam 226 is imaged onto the substrate W held by the wafer stage or substrate stage WT via the projection system PS and the reflective elements 228, 229.

[0066] There may generally be more elements in the illumination optical unit IL and the projection system PS than those shown. The grating spectral filter 240 may optionally be present depending on the type of lithographic apparatus. In addition, there may be more mirrors than the Figure 2 mirrors shown in Figure 2 For example, compared to those shown in

[0067] As Figure 2 illustrated, the collector optics CO is depicted as a nested collector having grazing-incidence reflectors 253, 254, and 255, which is merely an example of a collector (or collector mirror). The grazing-incidence reflectors 253, 254, and 255 are arranged to be axially symmetric about the optical axis O, and this type of collector optics CO is preferably used in combination with a discharge-produced plasma source commonly referred to as a DPP source.

[0068] Exemplary lithography cell

[0069] Figure 3FIG. 300 shows a lithography cell 300 according to some embodiments, sometimes also referred to as a lithography cell or cluster. The lithography apparatus 100 or 100' may form part of the lithography cell 300. The lithography cell 300 may also include one or more apparatuses for performing pre-exposure processes and post-exposure processes on a substrate. In some examples, these apparatuses include a spin coater SC for depositing a resist layer, a developer DE for developing the exposed resist, a chill plate CH, and a bake plate BK. A substrate transfer device or robot RO picks up substrates from the input / output ports I / O1, I / O2, moves the substrates between different process apparatuses and transfers the substrates to the feed table LB of the lithography apparatus 100 or 100'. These apparatuses, often collectively referred to as the track, are under the control of a track control unit TCU, which is itself controlled by a management control system SCS, which also controls the lithography apparatus via a lithography control unit LACU. Thus, the different apparatuses can be operated to maximize throughput and processing efficiency.

[0070] Exemplary external cassette

[0071] The external transfer cassettes described herein are subjected to atmospheric pressure (i.e., the external transfer cassettes can be vacuum chambers) and are capable of directly interfacing (sealing) with other vacuum chambers at their access points. In addition, the external transfer cassettes described herein can be opened from the side to facilitate direct access by an industrial handling robot to an EUV internal transfer cassette (EIP) in the horizontal plane. The external transfer cassette may include one or more interfaces for directly pumping and venting the external transfer cassette using existing industrial hardware. Thus, since the EIP does not move in an atmospheric environment, contamination is reduced. In some aspects, the external transfer cassettes described herein can be consistent with the mechanical characteristics of transfer cassettes defined by Semiconductor Equipment and Materials International (SEMI) E100 and SEMI E152 standards. Thus, existing automation equipment (such as overhead hoist transport (OHT)) can be used to transport the external transfer cassettes.

[0072] Figure 4 FIG. 400 shows a schematic diagram of a processing system 400 according to some embodiments. The processing system 400 may be a transfer cassette processing system (e.g., an internal transfer cassette). The processing system 400 may interface with a vacuum environment apparatus, such as a lithography exposure apparatus (also referred to as a scanner). The processing system 400 may receive an external transfer cassette 402 containing an internal transfer cassette 418 and may transfer the internal transfer cassette 418 to the lithography exposure apparatus. The lithography exposure apparatus is configured to perform lithography exposure using a reticle stored in the internal transfer cassette 418.

[0073] In one aspect, the external transfer cassette 402 includes a channel door 420 and a housing 422. The channel door 420 and the housing 422 form an enclosed space 430. The enclosed space 430 is configured to store an internal transfer cassette 418 (such as an EIP). A reticle can be stored in the internal transfer cassette 418. The channel door 420 can be configured to provide access to the interior of the enclosed space 430 for placing or removing the internal transfer cassette 418. The channel door 420 can be located in a vertical plane to allow the formation of a front channel (opposed to a bottom channel or a top channel). The front channel allows connection to a vacuum environment by the processor system 400 as described below. The external transfer cassette 402 can also include a flange 424. The external transfer cassette 402 is configured to be clamped and transported by the flange 424. In some aspects, an OHT transfer cassette processor module can be used to transport the external transfer cassette 402.

[0074] In some embodiments, the housing 422 can include a supply interface 416. The enclosed space 430 can be evacuated and purged through the supply interface 416. Although Figure 4 one supply interface is shown, it should be understood that the housing 422 can include more than one supply interface. The supply interface 416 can include a valve that controls the airflow into and out of the enclosed space 430 of the external transfer cassette 402. The housing 422 can include supply seals 428a and 428b. The external transfer cassette 402 can be fully sealed during transportation. In some aspects, the enclosed space 430 is capable of maintaining a vacuum pressure in the range of between about 1.3 Pa and about 4.3 Pa. By fully sealing the external transfer cassette 402 and processing the internal transfer cassette 418 in a vacuum, the risk of contamination from reticle particles, chemical elements, and / or outgassing can be avoided.

[0075] The processing system 400 can include an in-vacuum robot (IVR) 410 configured to transfer the internal transfer cassette 418 from the interior of the external transfer cassette 402 to an in-vacuum environment. The IVR 410 can include a gripper 426. The gripper 426 can be configured to move the internal transfer cassette 418 from the enclosed space 430. The gripper 426 can enter the interior of the external transfer cassette 402 through the channel door 420. In some aspects, the gripper 426 can be configured to move in the XY plane (e.g., linearly move in the y direction).

[0076] In some embodiments, the processing system 400 may include a gate valve 414. The gate valve 414 may be part of a lifting system. According to some aspects, the lifting system may include a lifting mechanism. For example, the gate valve 414 may include a cable (or lifting belt) (not shown). The gate valve 414 may move in the z direction. The gate valve 414 may be controlled by a control system. In the open (or raised) state, the gate valve 414 provides an opening for the IVR 410 to access the external transfer cassette 402. The gate valve 414 may include seal interfaces 442a and 442b. In some aspects, the seal interfaces 442a and 442b may be provided on the housing 422. The seal interfaces 442a and 442b may have any shape (e.g., circular).

[0077] In some embodiments, the external transfer cassette 402 may be located on a first support (or stage) 404. In some embodiments, an OHT transfer cassette processor module may be used to position the external transfer cassette 402 on the first support 404. For example, the external transfer cassette 402 may descend onto the first support 404 as shown by the arrow marked A in Figure 4 the figure.

[0078] The processor system 400 may further include a second support 412. The gate valve 414 may be coupled to the first stage 404 and the second stage 414 via supports 444a, 444b, and 444c.

[0079] In some embodiments, a stage 406 may be used to move the pump and exhaust supply device 408 close to the external transfer cassette 402 to provide a seal between the supply device 408 and the external transfer cassette 402. The stage 406 may move in the y direction. In some aspects, supply seals 428a and 428b may be positioned on the outer surface of the housing 422 and are configured to provide a seal between the pump and exhaust supply device and the stage 406 and the external transfer cassette 402.

[0080] Figure 5A is a schematic diagram of an external transfer cassette 502 according to some embodiments. In one aspect, the external transfer cassette 502 includes a channel door 520 and a housing 522. The channel door 520 and the housing 522 form an enclosed space 530. The enclosed space 530 is configured to store an internal transfer cassette 518. The external transfer cassette 502 may further include one or more supports 532 configured to hold the internal transfer cassette 518 when the channel door 520 is in the lowered position. In some aspects, the channel door 520 may be lowered to provide access to the enclosed space 530 via an opening 536. The channel door 520 may be configured to move linearly in the z direction. The channel door 520 may be actuated by a controller.

[0081] In some embodiments, the access door 520 may include one or more vertical supports 534 (e.g., studs formed on the inner surface of the access door 520). When the access door is in the closed position, the vertical supports 534 may hold the inner transfer cassette 518. In some aspects, the opening 536 may be sized in the range from about 45 mm to about 85 mm. The width of the outer transfer cassette 502 may be in the range from about 220 mm to about 265 mm. It should be understood that for larger wafers, the opening 536 and the width of the outer transfer cassette 502 may be made larger. For example, the first range may be applicable to the RSP200 transfer cassette, while larger wafer FOUP containers may require a larger range.

[0082] Figure 5B FIG. is a schematic view of an outer transfer cassette 502 with an access door 520 in the lowered position according to some embodiments. The IVR (e.g., IVR 410) may remove the inner transfer cassette 518 from the outer transfer cassette 502 via the opening 536. Before lowering the access door 520, the outer transfer cassette 502 may be evacuated and purged.

[0083] In some embodiments, the housing 522 may include a first supply interface 516a and a second supply interface 516b. The first supply interface 516a may be used to evacuate the enclosed space 530. The second supply interface 516b may be used to purge the enclosed space 530. Once the enclosed space 530 has been evacuated and purged, the outer transfer cassette 502 may be used as a load port for a vacuum environment apparatus. Thus, additional equipment (such as an EIP processor) may not be required to transfer the inner transfer cassette 518 to the vacuum environment apparatus.

[0084] Figure 6 FIG. is a schematic view showing an outer transfer cassette 602 according to some embodiments. The outer transfer cassette 602 includes an access door 620 and a housing 622. The access door 620 and the housing 622 form an enclosed space 630. The enclosed space 630 is configured to store an inner transfer cassette 618. The outer transfer cassette 602 may further include one or more supports 632 configured to hold the inner transfer cassette 618. The one or more supports 632 may be one or more studs formed on the inner surface of the housing 622. In some aspects, the access door 620 may be a removable door. Thus, the access door 620 may be removed to provide access to the enclosed space 630 via the opening 636. The access door 620 may be configured to be removed using an external device. After the access door has been removed, the IVR (e.g., IVR 410) may remove the inner transfer cassette 618 from the outer transfer cassette 602.

[0085] In some embodiments, the outer shell 622 may include a first supply interface 616a and a second supply interface 616b. The first supply interface 616a may be used to evacuate the enclosed space 630. The second supply interface 616b may be used to purify the enclosed space 630. Once the enclosed space 630 is evacuated and purified, the external transfer cassette 602 can be used as a loading port for a vacuum environment device. Thus, the IVR can transfer the internal transfer cassette 618 to the vacuum environment device without using additional equipment.

[0086] Figure 7A FIG. is a schematic diagram showing an external transfer cassette 702 according to some embodiments. In some aspects, the external transfer cassette 702 includes a channel door 720 and an outer shell 722. The channel door 720 and the outer shell 722 form an enclosed space 730. The enclosed space 730 is configured to store the internal transfer cassette 718.

[0087] In some embodiments, the outer shell 722 may include a first supply interface 716a and a second supply interface 716b. The first supply interface 716a may be used to evacuate the enclosed space 730. The second supply interface 716b may be used to purify the enclosed space 730. Once the enclosed space 730 is evacuated and purified, the external transfer cassette 702 can be used as a loading port for a vacuum environment device.

[0088] In some embodiments, the channel door 720 may be a revolving door. The channel door 720 may be configured to rotate within the enclosed space 730 (i.e., within the external transfer cassette 702). The channel door 720 may be configured to rotate using an external device (not shown). In some aspects, the channel door 720 may be configured to generate a force (in the z-direction) using a high-pitch central threaded member to lock the internal transfer cassette 718. In some aspects, the channel door 720 may include a flexible plate 736 configured to generate a z-movement based on a 90-degree movement of a flexible member (flexible threaded member).

[0089] Figure 7B FIG. shows a cross-sectional view 700 of the external transfer cassette 702 along the Figure 7A line AA in Figure 7B FIG. In some aspects,

[0090] Figure 8AA schematic diagram of an external transfer cassette 802 according to some embodiments is shown. In some aspects, the external transfer cassette 802 includes a channel door 820 and a housing 822. The channel door 820 and the housing 822 form an enclosed space 830. The enclosed space 830 is configured to store an internal transfer cassette 818. The external transfer cassette 802 may further include one or more supports 832. The supports 832 are configured to hold the internal transfer cassette 818.

[0091] In some embodiments, the channel door 820 may be a rotating door. The channel door 820 may be configured to rotate outside the enclosed space 830 (i.e., outside the housing 822). The channel door 820 may be configured to rotate using an external device (not shown). The channel door 820 may include a rear door 820a, a front door 820b, and a plate 838. The rear door 820a and the front door 820b are coupled to the plate 838. This provides a force to hold the internal transfer cassette 818 within the external transfer cassette 802. The channel door 820 may be coupled to the housing 822 using soft seals 840a, 840b, 840c, and 840d.

[0092] In some embodiments, the channel door 820 may be configured to linearly move and rotate in an upward motion to provide access to the enclosed space 830 via a first opening 836a and a second opening 836b. In some aspects, the channel door 820 may be raised within a range between about 10 mm to about 20 mm or about 15 mm. Then, the channel door 820 may rotate. The first opening 836a may be used to remove the internal transfer cassette 818. The second opening 836b may be used to evacuate the enclosed space 830. In some aspects, the second opening 836b may also be used to purify the enclosed space 830. The channel door 820 may include one or more vertical supports 834. In some aspects, the supports 834 may be used to apply a force on the transfer cassette 818. For example, the transfer cassette 818 may have a top cover with a built-in spring plunger that, when a force is applied, can press onto an internal reticle to hold the internal reticle by friction, thereby preventing the reticle from sliding in the x and / or y directions due to external acceleration.

[0093] Figure 8B A schematic diagram of an external transfer cassette 802 according to some embodiments is shown, where the channel door 820 is in a raised position. In some aspects, the channel door 820 may be configured to linearly move in a vertical motion. For example, the channel door 820 may move upward as shown by the arrow marked A in Figure 8B as shown.

[0094] Figure 8C is a schematic diagram showing a cross-sectional view of the external transfer cassette 802 along a horizontal plane. In some aspects, the channel door 820 may be along Figure 8Crotate in the direction indicated by the arrow labeled B in [the figure] to provide access to the first opening 836a and the second opening 836b.

[0095] Figure 9 FIG. shows a schematic view of an external transfer cassette 902 according to some embodiments. In some aspects, the external transfer cassette 902 includes a channel door 920 and a housing 922. The channel door 920 and the housing 922 form an enclosed space 930. In some embodiments, the enclosed space 930 is configured to store an internal transfer cassette 918. The external transfer cassette 902 may further include one or more supports 932 configured to hold the internal transfer cassette 918. In some aspects, the channel door 920 may be a removable door. Thus, the channel door 920 can be removed to provide access to the enclosed space 930 through the opening 936. The channel door 920 can be configured to be removed using an external device. After the channel door 920 has been removed, an IVR (such as IVR 410) can remove the internal transfer cassette 918 from the external transfer cassette 902. In some aspects, the channel door 920 can be removed in the z-direction (e.g., by an external device). In some aspects, the opening 936 can also be used to evacuate the enclosed space 930 and purify the enclosed space 930 with a purifying gas (such as nitrogen). Thus, the housing 922 may not include a separate supply interface.

[0096] Figure 10 FIG. shows a schematic view of a processing system 1000 according to some embodiments. The processing system 1000 can be a transfer cassette processing system (e.g., an internal transfer cassette). The processing system 1000 can interface with a vacuum environment device, such as a lithography exposure device (also referred to as a scanner). The processing system 1000 can receive an external transfer cassette 1002 containing an internal transfer cassette 1018 and can transfer the internal transfer cassette 1018 to the lithography exposure device. The lithography exposure device is configured to perform lithography exposure using a mask stored in the internal transfer cassette 1018. In some embodiments, the external transfer cassette 1002 can be similar to Figure 9 the external transfer cassette 902.

[0097] In some embodiments, the processing system 1000 can include an IVR 1010 configured to transfer the internal transfer cassette 1018 from the interior of the external transfer cassette 1002 to a vacuum inner environment. The IVR 1010 can include a gripper 1026. The gripper 1026 can be configured to move the internal transfer cassette 1018 from the enclosed space 1030. The gripper 1026 can enter the interior of the external transfer cassette 1002 via the channel door 1020. In some aspects, the gripper 1026 is configured to move in the XY plane.

[0098] In some embodiments, the processing system 1000 may include a gate valve 1014. The gate valve 1014 may be part of a lifting system. According to some aspects, the lifting system may include a lifting mechanism. The gate valve 1014 may include a cable (or lifting belt) (not shown). The gate valve 1014 may move in the z direction. The gate valve 1014 may be controlled by a control system. In the open (or raised) state, the gate valve 1014 provides an opening for the IVR 1010 to the enclosed space 1030. The gate valve 1014 may include seal interfaces 1042a and 1042b. In some aspects, the seal interfaces 1042a and 1042b may be provided on the housing 1022. The seal interfaces 1042a and 1042b may have any shape (e.g., circular). In some embodiments, the gate valve 1014 may include a supply device 1008 (i.e., a pump and a purification supply device).

[0099] In some embodiments, the external transfer cassette 1002 may be positioned on a first support (or stage) 1004. The processor system 1000 may further include a second support 1012. The gate valve 1014 may be coupled to the first stage 1004 and the second stage 1014 by support devices 1044a, 1044b, and 1044c.

[0100] In some embodiments, the stage 1006 may be used to provide support for the external transfer cassette 1002. In some embodiments, an OHT transfer cassette processor module may be used to position the external transfer cassette 1002 on the first support 1004. Figure 10 The removed channel door 1020 is shown. The channel door 1020 may be removed in the z direction.

[0101] Figure 11 is a flowchart of a method 1100 for processing an internal transfer cassette according to some embodiments. It should be understood that not all operations need to be performed or performed in the order shown.

[0102] In step 1102, the patterning device is received (retained or held) in a first container (i.e., the internal transfer cassette).

[0103] In step 1104, the first container may be maintained in a predetermined environment, such as a clean and controlled environment.

[0104] In step 1106, the first container may be received in a second container (e.g., an external transfer cassette).

[0105] In step 1108, the second container may be maintained at a second vacuum level, for example, the vacuum range may be from about 1.3 PA to about 4.3 PA.

[0106] In step 1110, the second container is transported by gripping a flange of the second container located on the outside of the second container.

[0107] In step 1112, gas is introduced into the second container through a purge valve connected to a first external vacuum environment.

[0108] In step 1114, gas is removed from the second container through a vacuum valve connected to the first external vacuum environment.

[0109] In step 1116, the first container is removed from the second container through an opening of the second container. For example, the first container can be removed through a passage door of the second container.

[0110] In an optional aspect, in step 1108, the transfer cassette can be represented as being in a vacuum, where the transfer cassette sealed to be in a vacuum reaches a device for introducing a cleaning gas, such that the transfer cassette is brought to the atmosphere and then evacuated again. If performed, this step can be used to purge the transfer cassette from a storage state. When this operation is performed, method 1100 moves to step 1116 which is completed in a vacuum state.

[0111] Various embodiments of the present system and method are disclosed in the following numbered list:

[0112] 1. A system, comprising:

[0113] A first container configured to receive a patterning device and maintain a predetermined environment within the first container; and

[0114] A second container configured to receive the first container and maintain a vacuum within the second container, wherein the second container includes:

[0115] A flange located on the outside of the second container, wherein the second container is configured to be gripped and transported via the flange;

[0116] A first end including a vacuum valve and a purge valve, the vacuum valve being configured to facilitate removal of gas from the second container, the purge valve being configured to facilitate introduction of gas into the second container, wherein the vacuum valve and the purge valve are configured to be connected to a first external vacuum environment; and

[0117] A second end opposite the first end, the second end having an opening configured to allow removal of the first container from the second container through the opening.

[0118] 2. The system according to aspect 1, wherein the opening is configured to be closed and opened by a door.

[0119] 3. The system according to aspect 1, wherein the opening is configured to interface with a second external vacuum environment.

[0120] 4. The system according to aspect 2, wherein the door opens or closes in the z - direction.

[0121] 5. The system according to aspect 2, wherein a 90° rotation of the door opens or closes the door.

[0122] 6. The system according to aspect 5, wherein the 90° rotation is configured to be by rotation of a threaded member.

[0123] 7. The system according to aspect 2, wherein the door is raised and then rotated to open or close the door.

[0124] 8. A method, comprising:

[0125] Receiving a patterning device in a first container;

[0126] Maintaining the first container in a predetermined environment;

[0127] Receiving the first container in a second container;

[0128] Maintaining the second container at a vacuum level;

[0129] Transporting the second container via a flange located outside the second container;

[0130] Removing gas from the second container through a vacuum valve that interfaces with a first external vacuum environment;

[0131] Introducing gas into the second container through a purge valve that interfaces with the first external vacuum environment; and

[0132] Removing the first container from the second container through an opening.

[0133] 9. The method according to aspect 8, further comprising opening and closing the opening using a door.

[0134] 10. The method according to aspect 8, further comprising interfacing the opening with a second external vacuum environment.

[0135] 11. The method according to aspect 9, further comprising opening and closing the door in the z - direction.

[0136] 12. The method according to aspect 9, further comprising rotating the door 90° to open or close the door.

[0137] 13. The method according to aspect 12, further comprising using a threaded member to allow the 90° rotation.

[0138] 14. The method according to aspect 9 further comprises raising and rotating the door to open and close the door.

[0139] 15. An external transfer cassette, comprising:

[0140] A housing;

[0141] A flange located outside the housing, wherein the external transfer cassette is configured to be clamped and transported via the flange;

[0142] An end having an opening, wherein the opening is configured to allow removal of an internal transfer cassette stored in the external transfer cassette and to interface with an external vacuum environment; and

[0143] A channel door configured to seal the opening.

[0144] 16. The transfer cassette according to aspect 15, wherein the channel door is a rotatable door, and a 90° rotation of the channel door opens or closes the channel door.

[0145] 17. The transfer cassette according to aspect 16, wherein the channel door rotates outside the housing.

[0146] 18. The transfer cassette according to aspect 16, wherein the channel door rotates inside the housing.

[0147] 19. The transfer cassette according to aspect 15, wherein the channel door opens and closes in the z-direction.

[0148] 20. The transfer cassette according to aspect 15, wherein the channel door is detachable from the housing to provide access to the opening.

[0149] Although the lithographic apparatus may be specifically referred to herein in the context of use in IC manufacture, it should be understood that the lithographic apparatus described herein may have other applications such as the manufacture of integrated optical systems, guidance and detection patterns for magnetic domain memories, flat panel displays, LCDs, thin film magnetic heads, etc. Those skilled in the art will appreciate that in the context of such alternative applications, any use herein of the terms "wafer" or "die" may be considered to be synonymous with the more general terms "substrate" or "target portion" respectively. The substrates referred to herein may be processed, before or after exposure, in, for example, a track unit (a tool that typically applies a resist layer to a substrate and develops the exposed resist) and / or a metrology unit. Where applicable, the content of this document may be applied to these and other substrate processing tools. Additionally, the substrate may be processed more than once, for example in order to form a multi-layer IC, such that the term "substrate" as used herein may also refer to a substrate that already contains multiple processed layers.

[0150] Although embodiments of the present disclosure may have been specifically referred to above in the context of using them in optical lithography, it should be understood that embodiments of the present disclosure can be used in other applications (e.g., imprint lithography), and, where the context allows, are not limited to optical lithography. In imprint lithography, the topography of the patterning device defines the pattern formed on the substrate. The topography of the patterning device can be pressed into a resist layer provided to the substrate, and then the resist is cured by applying electromagnetic radiation, heat, pressure, or a combination thereof. After the resist is cured, the patterning device is removed from the resist, leaving a pattern therein.

[0151] It should be understood that the language or terminology herein is for the purpose of description and not of limitation, such that the terms or language of the present disclosure will be interpreted by those skilled in the relevant art(s) in light of the teachings herein.

[0152] The terms “radiation,” “radiation beam,” etc. may be used herein to encompass all types of electromagnetic radiation, such as ultraviolet (UV) radiation (e.g., having a wavelength λ of 365, 248, 193, 157, or 126 nm), extreme ultraviolet (EUV or soft X-ray) radiation (e.g., having a wavelength in the range of 5 nm - 20 nm, such as, for example, 13.5 nm), or hard X-rays operating at less than 5 nm, as well as beams of matter (such as ion beams or electron beams). The terms “light,” “irradiation,” etc. may refer to non-material radiation (e.g., photons, UV, X-rays, etc.). Generally, radiation having a wavelength between about 400 and about 700 nm is considered visible light radiation; radiation having a wavelength between about 780 nm - 3000 nm (or greater) is considered IR radiation. UV refers to radiation having a wavelength of about 100 nm - 400 nm. In lithography techniques, the term “UV” also applies to wavelengths that can be produced by mercury discharge lamps: G-line 436 nm; H-line 405 nm; and / or I-line 365 nm. Vacuum UV or VUV (i.e., UV that is absorbed by gas) refers to radiation having a wavelength of about 100 nm - 200 nm. Deep UV (DUV) generally refers to radiation having a wavelength range of 126 nm to 428 nm, and in some aspects, excimer lasers can produce DUV radiation for use within a lithographic apparatus. It should be understood that radiation having a wavelength in the range of, for example, 5 nm - 20 nm refers to radiation having a specific wavelength band, at least a portion of which is within the range of 5 nm - 20 nm.

[0153] It should be understood that the detailed description section (as opposed to the summary and abstract sections) is intended to be used in the interpretation of the claims. The summary and abstract sections may set forth one or more exemplary embodiments contemplated by the inventors, but not all exemplary embodiments, and thus the summary and abstract sections are not intended to limit the embodiments and the appended claims in any way.

[0154] The present disclosure has been described above in terms 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 have been arbitrarily defined herein. Alternative boundaries can be defined so long as the specific functions and their relationships are appropriately performed.

[0155] Although specific embodiments of the present disclosure have been described above, it should be understood that the embodiments of the present disclosure may be practiced in a manner different from that described. The description is intended to be illustrative, not restrictive. Thus, it will be apparent to those skilled in the art that the described present disclosure may be modified without departing from the scope of the claims set forth.

[0156] The foregoing description of specific embodiments will so fully reveal the general nature of the present disclosure that others can, by applying the knowledge within the skill of those in the art, readily modify and / or adapt various applications of these specific embodiments without undue experimentation and without departing from the general concept of the present disclosure. Therefore, such adaptations and modifications are intended to fall within the meaning and scope of the equivalents of the disclosed embodiments based on the teachings and guidance presented herein.

[0157] The breadth and scope of the subject matter protected should not be limited by any of the above-described exemplary embodiments, but should be defined only in accordance with the following claims and their equivalents.

Claims

1. A system, comprising: A first container configured to receive a patterning device and maintain a predetermined environment within the first container; And A second container configured to receive the first container and maintain a vacuum within the second container, wherein the second container comprises: A flange located outside the second container, wherein the second container is configured to be clamped and transported via the flange; A first end including a vacuum valve and a purge valve, the vacuum valve configured to facilitate removal of gas from the second container, the purge valve configured to facilitate introduction of gas into the second container, wherein the vacuum valve and the purge valve are configured to interface with a first external vacuum environment; and A second end opposite the first end having an opening configured to allow removal of the first container from the second container through the opening.

2. The system according to claim 1, wherein the opening is configured to be closed and opened by a door.

3. The system according to claim 1, wherein the opening is configured to interface with a second external vacuum environment.

4. The system according to claim 2, wherein: The door opens or closes in the z direction; A 90° rotation of the door opens or closes the door; The 90° rotation is configured to be rotated by a threaded member; and The door is raised and then rotated to open or close the door.

5. A method, comprising: Receiving a patterning device in a first container; Maintaining the first container in a predetermined environment; Receiving the first container in a second container; Maintaining the second container at a vacuum level; Transporting the second container via a flange located outside the second container; Removing gas from the second container through a vacuum valve interfacing with a first external vacuum environment; Introducing gas into the second container through a purge valve interfacing with the first external vacuum environment; and Removing the first container from the second container through an opening.

6. The method according to claim 5, further comprising: Opening and closing the opening using a door; Using the opening to interface with a second external vacuum environment; And Opening and closing the door in the z direction.

7. The method according to claim 6, further comprising rotating the door 90° to open or close the door.

8. The method according to claim 7, further comprising using a threaded member to allow the 90° rotation.

9. The method according to claim 6, further comprising raising and rotating the door to open and close the door.

10. An external transfer cassette, comprising: A housing; A flange located outside the housing, wherein the external transfer cassette is configured to be clamped and transported via the flange; An end having an opening configured to allow removal of an internal transfer cassette stored in the external transfer cassette and to interface with an external vacuum environment; And A channel door configured to seal the opening.

11. The transfer cassette according to claim 10, wherein the channel door is a rotatable door and a 90° rotation of the channel door opens or closes the channel door.

12. The transfer cassette according to claim 11, wherein the channel door rotates outside the housing.

13. The transfer cassette according to claim 11, wherein the channel door rotates inside the housing.

14. The transfer cassette according to claim 10, wherein the channel door opens and closes in the z direction.

15. The transfer cassette according to claim 10, wherein the channel door is detachable from the housing to provide access to the opening.

Images