Modular moveable loading station for a lithography apparatus

Abstract

A lithography system comprising a lithography apparatus and a modular moveable loading station is described. The loading station is configured to move relative to the lithography apparatus, and be coupled with the lithography apparatus at a location corresponding to a patterning device (e.g., reticle) load port. The loading station is modular and configured to be moveably coupled with the 5 lithography apparatus outside a footprint of a perimeter of the lithography apparatus at the location corresponding to the load port to accommodate different configurations of the lithography apparatus, and to facilitate maintenance of a common separation distance between the load port and a patterning device holder (e.g., a reticle stage) across the different configurations. The moveable modularity of the loading station facilitates a reduced footprint and / or volume of the lithography apparatus 0 compared to one or more footprints of prior lithography apparatuses.

Description

MODULAR MOVEABLE LOADING STATION FOR A LITHOGRAPHY APPARATUSCROSS-REFERENCE TO RELATED APPLICATIONS

[0001] This application claims priority of US application 63 / 673,944 which was filed on July 22, 2024 and which is incorporated herein in its entirety by reference.TECHNICAL FIELD

[0002] The description herein relates generally to a modular moveable loading station for a lithography apparatus.BACKGROUND

[0003] A lithography (e.g., projection) apparatus can be used, for example, in the manufacture of integrated circuits (ICs). In such a case, a patterning device (e.g., a reticle or mask) may contain or provide a pattern corresponding to an individual layer of the IC (“design layout”), and this pattern can be transferred onto a target portion (e.g. comprising one or more dies) on a substrate (e.g., silicon wafer) that has been coated with a layer of radiation-sensitive material (“resist”), by methods such as irradiating the target portion through the pattern on the patterning device. In general, a single substrate contains a plurality of adjacent target portions to which the pattern is transferred successively by the lithographic projection apparatus, one target portion at a time. In one type of lithographic projection apparatus, the pattern on the entire patterning device is transferred onto one target portion in one operation. Such an apparatus is commonly referred to as a stepper. In an alternative apparatus, commonly referred to as a step-and-scan apparatus, a projection beam scans over the patterning device in a given reference direction (the “scanning” direction) while synchronously moving the substrate parallel or anti-parallel to this reference direction. Different portions of the pattern on the patterning device are transferred to one target portion progressively. One or more patterning devices are provided to the lithography apparatus as needed to form the IC.SUMMARY

[0004] Lithography systems (and corresponding methods) comprising a lithography apparatus and a modular moveable loading station are described. The loading station is configured to move relative to the lithography apparatus, and be coupled with the lithography apparatus at a location corresponding to a patterning device (e.g., reticle) load port. The loading station is modular and configured to be moveably coupled with the lithography apparatus outside a footprint of a perimeter of the lithography apparatus at the location corresponding to the load port to accommodate different configurations of the lithography apparatus, and to facilitate maintenance of a common separation distance between the load port and a patterning device holder (e.g., a reticle stage) across the different configurations. The moveable modularity of the loading station facilitates a reduced footprint and / orvolume of the lithography apparatus compared to one or more footprints of prior lithography apparatuses, among other advantages.

[0005] According to an embodiment, there is provided a lithography system. The lithography system comprises a lithography apparatus, a modular moveable loading station, and / or other components. The lithography apparatus is configured to transfer a pattern from a patterning device to a substrate. The lithography apparatus comprises a patterning device load port and / or other components. The moveable loading station is configured to move relative to the lithography apparatus, and be coupled with the lithography apparatus at a location corresponding to the load port. The loading station is configured to receive the patterning device for movement to the load port.

[0006] In some embodiments, the moveable loading station comprises wheels, one or more rails, a track, and / or a retractable shelf configured to facilitate movement of the moveable loading station relative to the lithography apparatus.

[0007] In some embodiments, the lithography apparatus comprises a holder configured to hold the patterning device during patterning, there being a separation distance between the load port and the holder. The holder may comprise a reticle stage of the lithography apparatus, for example.

[0008] In some embodiments, the loading station is modular and configured to be moveably coupled with the lithography apparatus outside a footprint of a perimeter of the lithography apparatus at the location corresponding to the load port to accommodate different configurations of the lithography apparatus, and to facilitate maintenance of the separation distance between the load port and the holder across the different configurations. The different configurations may correspond to different numerical apertures (NA) associated with the lithography apparatus, for example.

[0009] In some embodiments, the lithography system comprises a handling system. The handling system comprises a first handler configured to move the patterning device from the loading station to the load port, and a second handler configured to move the patterning device from the load port to the holder. In some embodiments, the patterning device is held within an inner pod and an outer pod in the loading station. The first handler is configured to move the outer pod to the load port, and the second handler is configured to move the patterning device from the inner pod at the load port to the holder.

[0010] Hardware of the handling system is substantially the same across different configurations of lithography apparatuses because the modular and moveably coupled loading station facilitates maintenance of the separation distance between the load port and the holder across different configurations of the lithography apparatus.

[0011] In some embodiments, the first handler comprises a cartesian robot. In some embodiments, the first handler comprises a pick and place robot. In some embodiments, the first handler comprises an overhead hoist transport. In some embodiments, the first handler comprises first and second rails configured to facilitate movement of the patterning device from the loading station to the load port in two dimensions. The first and second rails may comprise a linear rail oriented in an x or y dimensionrelative to the lithography apparatus, and a z-rail oriented in a z dimension relative to the lithography apparatus, respectively, for example.

[0012] In some embodiments, the modular and movably coupled loading station is configured to reduce or eliminate a need for a selective compliance assembly robot arm (SCARA) in the first handler because a distance between the loading station and the load port is reduced compared to a corresponding distance in prior lithography apparatuses.

[0013] In some embodiments, the lithography apparatus comprises an extreme ultra violet (EUV) scanner, and the patterning device comprises a reticle.

[0014] In some embodiments the loading station is modular and configured to be moveably coupled with the lithography apparatus to facilitate a reduced footprint and / or volume of the lithography apparatus compared to one or more footprints of prior lithography apparatuses.

[0015] In some embodiments, the lithography apparatus is configured to receive the substrate. The substrate has a photoresist layer. The lithography apparatus is configured to direct radiation from a radiation source toward the substrate via the patterning device to transfer the pattern from the patterning device onto the photoresist layer; and facilitate removal a portion of the photoresist layer to form the pattern over the substrate, to form one or more integrated circuits or chips in or on the substrate.

[0016] According to another embodiment, there is provided a lithography method comprising moving a moveable loading station relative to a lithography apparatus, and coupling the loading station to the lithography apparatus. The lithography apparatus is configured to transfer a pattern from a patterning device to a substrate, with the lithography apparatus comprising a patterning device load port. The loading station is coupled with the lithography apparatus at a location corresponding to the load port. The loading station is configured to receive the patterning device for movement to the load port. In some embodiments, one or more additional operations performed by the lithography apparatus are included in the lithography method.BRIEF DESCRIPTION OF THE DRAWINGS

[0017] The accompanying drawings, which are incorporated in and constitute a part of the specification, illustrate one or more embodiments and, together with the description, explain these embodiments. Embodiments of the invention will now be described, by way of example only, with reference to the accompanying schematic drawings in which corresponding reference symbols indicate corresponding parts, and in which:

[0018] Fig. 1 schematically depicts a lithography apparatus, according to an embodiment.

[0019] Fig. 2 schematically depicts an embodiment of a lithographic cell or cluster, according to an embodiment.

[0020] Fig. 3 illustrates a portion of an extreme ultra violet (EUV) lithography apparatus, according to an embodiment.

[0021] Fig. 4 illustrates another example lithography apparatus (e.g., similar to an or the same as the lithography apparatus shown in Fig. 1, with components similar to and / or the same as the components of the lithography apparatus shown in Fig. 3), according to an embodiment.

[0022] Fig. 5 illustrates a lithography system, according to an embodiment.

[0023] Fig. 6 illustrates another view of the lithography system shown in Fig. 5, including a lithography apparatus, a loading station, a handing system, and / or other components, according to an embodiment.

[0024] Fig. 7 illustrates another view of a portion of a possible embodiment of the lithography system shown in Fig. 6 and Fig. 5, according to an embodiment.

[0025] Fig. 8 illustrates maintenance of common separation distance between load port(s) and patterning device holder(s) (e.g., reticle stages) across different configurations of lithography apparatuses, according to an embodiment.

[0026] Fig. 9 illustrates a lithography method, according to an embodiment.

[0027] Fig. 10 is a block diagram of an example computer system, according to an embodiment.DETAILED DESCRIPTION

[0028] In general, a mask or reticle may be a transparent block of material that is covered with a pattern defined by a different, opaque material. Or a mask or reticle may be an opaque block of material coated with a patterned mirror, for example. Various masks are loaded into a lithography apparatus and used to form layers of a semiconductor device. The pattern defined on a given mask or reticle corresponds to features produced in one or more layers of the semiconductor device. Often, a plurality of masks or reticles are automatically loaded into a lithography apparatus during manufacturing and used to form corresponding layers of a semiconductor device.

[0029] Different lithography apparatuses often use drastically different hardware to load and / or handle reticles. Hardware differences are driven by different lithography apparatus configurations, which typically correspond to different numerical apertures (NA) associated with the lithography apparatuses, even though these lithography apparatuses have the same general design and processing requirements. Unfortunately, reticle handling hardware is often considered only after the patterning related portions of a lithography apparatus have been designed, and is only allowed to utilize leftover available space. This leftover available space differs between lithography apparatuses (e.g., between lithography apparatuses associated with different NA’s), which forces different design solutions.

[0030] Ideal reticle handling hardware would be common from lithography apparatus to lithography apparatus, and / or be flexible to accommodate lithography apparatuses with different configurations (e.g., for different NA’s).

[0031] Advantageously, the lithography systems (and corresponding methods) described herein facilitate commonality and flexibility in reticle handling hardware. The lithography systems (and corresponding methods) described herein provide a new design which meets reticle handlingrequirements, but in a condensed machine volume space compared to prior hardware. By reducing the required hardware volume, it is feasible to reserve a common volume across lithography apparatuses having different configurations (e.g., associated with different NA’s). As described herein, the present systems (and corresponding methods) comprise a lithography apparatus and a modular moveable loading station. The loading station is configured to move relative to the lithography apparatus, and be coupled with the lithography apparatus at a location corresponding to a patterning device (e.g., reticle) load port. The loading station is modular and configured to be moveably coupled with the lithography apparatus outside a footprint of a perimeter of the lithography apparatus at the location corresponding to the load port to accommodate different configurations of the lithography apparatus, and to facilitate maintenance of a common separation distance between the load port and a patterning device holder (e.g., a reticle stage) across the different configurations. The moveable modularity of the loading station facilitates a reduced footprint and / or volume of the lithography apparatus compared to one or more footprints of prior lithography apparatuses.

[0032] Although specific reference may be made in this text to the manufacture of integrated circuits (ICs), it should be understood that the description herein has many other possible applications. For example, it may be employed in the manufacture of integrated optical systems, guidance and detection patterns for magnetic domain memories, liquid-crystal display panels, thin-film magnetic heads, etc. The skilled artisan will appreciate that, in the context of such alternative applications, any use of the terms “reticle”, “wafer” or “die” in this text should be considered as interchangeable with the more general terms “mask”, “substrate” and “target portion”, respectively. In addition, any use of the terms “reticle” or “mask” herein may be considered synonymous with the more general term “patterning device.”

[0033] As an introduction, prior to transferring a pattern from a patterning device such as a mask to a substrate, the substrate may undergo various procedures, such as priming, resist coating and a soft bake. After exposure, the substrate may be subjected to other procedures (“post-exposure procedures”), such as a post-exposure bake (PEB), development, a hard bake and measurement and / or other inspection of the transferred pattern. This array of procedures is used as a basis to make an individual layer of a device, e.g., an IC. The substrate may then undergo various processes such as etching, ion-implantation (doping), metallization, oxidation, chemical mechanical polishing, etc., all intended to finish an individual layer of the device. If several layers are required in the device, then the whole procedure, or a variant thereof, is repeated for each layer. Eventually, a device will be present in each target portion on the substrate. These devices are then separated from one another by a technique such as dicing or sawing, whence the individual devices can be mounted on a carrier, connected to pins, etc.

[0034] Manufacturing semiconductor devices typically involves processing a substrate (e.g., a semiconductor wafer) using a number of fabrication processes to form various features and multiple layers of the devices. Such layers and features are typically manufactured and processed using, e.g.,deposition, lithography, etch, chemical mechanical polishing, ion implantation, and / or other processes. Multiple devices may be fabricated on a plurality of dies on a substrate and then separated into individual devices. This device manufacturing process may be considered a patterning process. A patterning process involves a patterning step, such as optical and / or nanoimprint lithography using a patterning device in a lithography apparatus, to transfer a pattern on the patterning device to a substrate and typically, but optionally, involves one or more related pattern processing steps, such as resist development by a development apparatus, baking of the substrate using a bake tool, etching using the pattern using an etch apparatus, etc. One or more metrology processes are typically involved in the patterning process.

[0035] Lithography is a step in the manufacturing of devices such as ICs, where patterns formed on substrates define functional elements of the devices, such as microprocessors, memory chips, etc. Similar lithographic techniques are also used in the formation of flat panel displays, micro-electro mechanical systems (MEMS) and other devices.

[0036] Fig. 1 schematically depicts an embodiment of a lithography apparatus LA that may be included in and / or associated with the present systems and / or methods. The apparatus comprises: an illumination system (illuminator) IL configured to condition a radiation beam B (e.g., extreme ultraviolet (EUV) radiation); a holder comprising a support structure (e.g., a mask table) MT configured to support a patterning device (e.g. a mask) MA connected to a first positioner PM configured to accurately position the patterning device in accordance with certain parameters; a substrate table (e.g. a wafer table) WT (e.g., WTa, WTb or both) configured to hold a substrate (e.g. a resist-coated wafer) W and coupled to a second positioner PW configured to accurately position the substrate in accordance with certain parameters; and a projection system (e.g. a refractive projection lens system) PS configured to project a pattern imparted to the radiation beam B by patterning device MA onto a target portion C (e.g. comprising one or more dies and often referred to as fields) of the substrate W. The projection system is supported on a reference frame (RF). As depicted, the apparatus is of a transmissive type (e.g. employing a transmissive mask). Alternatively, the apparatus may be of a reflective type (e.g. employing a programmable mirror array of a type as referred to above, or employing a reflective mask).

[0037] The illuminator IL receives a beam of radiation from a radiation source SO. The source and the lithography apparatus may be separate entities, for example when the source is an excimer laser. In such cases, the source is not considered to form part of the lithography apparatus and the radiation beam is passed from the source SO to the illuminator IL with the aid of a beam delivery system BD comprising for example suitable directing mirrors and / or a beam expander. In other cases, the source may be an integral part of the apparatus, for example when the source is a mercury lamp. The source SO and the illuminator IL, together with the beam delivery system BD if required, may be referred to as a radiation system.

[0038] The illuminator IL may alter the intensity distribution of the beam. The illuminator may bearranged to limit the radial extent of the radiation beam such that the intensity distribution is non-zero within an annular region in a pupil plane of the illuminator IL. Additionally or alternatively, the illuminator IL may be operable to limit the distribution of the beam in the pupil plane such that the intensity distribution is non-zero in a plurality of equally spaced sectors in the pupil plane. The intensity distribution of the radiation beam in a pupil plane of the illuminator IL may be referred to as an illumination mode.

[0039] The illuminator IL may comprise adjuster AD configured to adjust the (angular / spatial) intensity distribution of the beam. Generally, at least the outer and / or inner radial extent (commonly referred to as o-outer and o-inncr. respectively) of the intensity distribution in a pupil plane of the illuminator can be adjusted. The illuminator IL may be operable to vary the angular distribution of the beam. For example, the illuminator may be operable to alter the number, and angular extent, of sectors in the pupil plane wherein the intensity distribution is non-zero. By adjusting the intensity distribution of the beam in the pupil plane of the illuminator, different illumination modes may be achieved. For example, by limiting the radial and angular extent of the intensity distribution in the pupil plane of the illuminator IL, the intensity distribution may have a multi-pole distribution such as, for example, a dipole, quadrupole or hexapole distribution. A desired illumination mode may be obtained, e.g., by inserting an optic which provides that illumination mode into the illuminator IL or using a spatial light modulator.

[0040] The illuminator IL may be operable to alter the polarization of the beam and may be operable to adjust the polarization using adjuster AD. The polarization state of the radiation beam across a pupil plane of the illuminator IL may be referred to as a polarization mode. The use of different polarization modes may allow greater contrast to be achieved in the image formed on the substrate W. The radiation beam may be unpolarized. Alternatively, the illuminator may be arranged to linearly polarize the radiation beam. The polarization direction of the radiation beam may vary across a pupil plane of the illuminator IL. The polarization direction of radiation may be different in different regions in the pupil plane of the illuminator IL. The polarization state of the radiation may be chosen in dependence on the illumination mode. For multi-pole illumination modes, the polarization of each pole of the radiation beam may be generally perpendicular to the position vector of that pole in the pupil plane of the illuminator IL. For example, for a dipole illumination mode, the radiation may be linearly polarized in a direction that is substantially perpendicular to a line that bisects the two opposing sectors of the dipole. The radiation beam may be polarized in one of two different orthogonal directions, which may be referred to as X-polarized and Y-polarized states. For a quadrupole illumination mode, the radiation in the sector of each pole may be linearly polarized in a direction that is substantially perpendicular to a line that bisects that sector. This polarization mode may be referred to as XY polarization. Similarly, for a hexapole illumination mode the radiation in the sector of each pole may be linearly polarized in a direction that is substantially perpendicular to a line that bisects that sector. This polarization mode may be referred to as TE polarization.

[0041] In addition, the illuminator IL generally comprises various other components, such as an integrator IN and a condenser CO. The illumination system may include various types of optical components, such as refractive, reflective, magnetic, electromagnetic, electrostatic, or other types of optical components, or any combination thereof, for directing, shaping, or controlling radiation. Thus, the illuminator provides a conditioned beam of radiation B, having a desired uniformity and intensity distribution in its cross section.

[0042] The holder or support structure MT supports the patterning device in a manner that depends on the orientation of the patterning device, the design of the lithography apparatus, and other conditions, such as for example whether or not the patterning device is held in a vacuum environment. The support structure may use mechanical, vacuum, electrostatic or other clamping techniques to hold the patterning device. The support structure may be a frame or a table, for example, which may be fixed or movable as required. The support structure may ensure that the patterning device is at a desired position, for example with respect to the projection system.

[0043] The term “patterning device” used herein should be broadly interpreted as referring to any device that can be used to impart a pattern in a target portion of the substrate. A patterning device may be any device that can be used to impart a radiation beam with a pattern in its cross-section to create a pattern in a target portion of the substrate. It should be noted that the pattern imparted to the radiation beam may not exactly correspond to the desired pattern in the target portion of the substrate, for example if the pattern includes phase-shifting features or so called assist features. Generally, the pattern imparted to the radiation beam will correspond to a particular functional layer in a device being created in a target portion of the device, such as an integrated circuit. A patterning device may be transmissive or reflective. Examples of patterning devices include reticles or masks.

[0044] The projection system PS may comprise a plurality of optical (e.g., lens) elements and may further comprise an adjustment mechanism configured to adjust one or more of the optical elements to correct for aberrations (phase variations across the pupil plane throughout the field). To achieve this, the adjustment mechanism may be operable to manipulate one or more optical (e.g., lens) elements within the projection system PS in one or more different ways. The projection system may have a coordinate system wherein its optical axis extends in the z direction. The adjustment mechanism may be operable to do any combination of the following: displace one or more optical elements; tilt one or more optical elements; and / or deform one or more optical elements. Displacement of an optical element may be in any direction (x, y, z, or a combination thereof). Tilting of an optical element is typically out of a plane perpendicular to the optical axis, by rotating about an axis in the x and / or y directions although a rotation about the z axis may be used for a non-rotationally symmetric aspherical optical element. Deformation of an optical element may include a low frequency shape (e.g. astigmatic) and / or a high frequency shape (e.g. free form aspheres). Deformation of an optical element may be performed for example by using one or more actuators to exert force on one or more sides of the optical element and / or by using one or more heating elements to heat one or more selectedregions of the optical element. In general, it may not be possible to adjust the projection system PS to correct for apodization (transmission variation across the pupil plane). The transmission map of a projection system PS may be used when designing a patterning device (e.g., mask) MA for the lithography apparatus LA. Using a computational lithography technique, the patterning device MA may be designed to at least partially correct for apodization.

[0045] The lithography apparatus may be of a type having two (dual stage) or more tables (e.g., two or more substrate tables WTa, WTb, two or more patterning device tables, a substrate table WTa and a table WTb below the projection system without a substrate that is dedicated to, for example, facilitating measurement, and / or cleaning, etc.). In such “multiple stage” machines, the additional tables may be used in parallel, or preparatory steps may be carried out on one or more tables while one or more other tables are being used for exposure. For example, alignment measurements using an alignment sensor AS and / or level (height, tilt, etc.) measurements using a level sensor LS may be made.

[0046] In operation of the lithography apparatus, a radiation beam is conditioned and provided by the illumination system IL. The radiation beam B is incident on the patterning device (e.g., reticle or mask) MA, which is held on the support structure (e.g., mask table) MT. Having traversed 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. With the aid of the second positioner PW and position sensor IF (e.g., an interferometric device, linear encoder, 2-D encoder, or capacitive sensor), the substrate table WT can be moved accurately, e.g. to position different target portions C in the path of the radiation beam B. Similarly, the first positioner PM and another position sensor (which is not explicitly depicted in Fig. 1) can be used to accurately position the patterning device MA with respect to the path of the radiation beam B, e.g. after mechanical retrieval from a mask library, or during a scan. In general, movement of the support structure MT may be realized 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 realized 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 support structure MT may be connected to a short-stroke actuator only, or may be fixed. Patterning device MA and substrate W may be aligned using patterning device alignment marks Ml, M2 and substrate alignment marks Pl, P2. Although the substrate alignment marks as illustrated occupy dedicated target portions, they may be located in spaces between target portions (these are known as scribe-lane alignment marks). Similarly, in situations in which more than one die is provided on the patterning device MA, the patterning device alignment marks may be located between the dies.

[0047] The depicted apparatus may be used in step mode or scan mode. In step mode, the support structure MT and the substrate table WT are kept essentially stationary, while a pattern imparted to the radiation beam is projected onto a target portion C at one time (i.e. a single static exposure). Thesubstrate table WT is then shifted in the X and / or Y direction so that a different target portion C can be exposed. In step mode, the maximum size of the exposure field limits the size of the target portion C imaged in a single static exposure. In scan mode, the support structure MT and the substrate table WT are scanned synchronously while a pattern imparted to the radiation beam 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 MT may be determined by the (de-) magnification and image reversal characteristics of the projection system PS. In scan mode, the maximum size of the exposure field limits the width (in the non-scanning direction) of the target portion in a single dynamic exposure, whereas the length of the scanning motion determines the height (in the scanning direction) of the target portion. In another mode, the support structure MT is kept essentially stationary holding a programmable patterning device, and the substrate table WT is moved or scanned while a pattern imparted to the radiation beam is projected onto a target portion C. In this mode, generally a pulsed radiation source is employed, and the programmable patterning device is updated as required after each movement of the substrate table WT or in between successive radiation pulses during a scan. This mode of operation can be readily applied to maskless lithography that utilizes programmable patterning device, such as a programmable mirror array of a type as referred to above. Combinations and / or variations on the above-described modes of use or entirely different modes of use may also be employed.

[0048] A substrate may be processed, before or after exposure, in for example a track (a tool that typically applies a layer of resist to a substrate and develops the exposed resist) or a metrology or inspection tool. Where applicable, the disclosure herein may be applied to such and other substrate processing tools. Further, the substrate may be processed more than once, for example in order to create a multi-layer IC, so that the term substrate used herein may also refer to a substrate that already includes multiple processed layers.

[0049] The terms “radiation” and “beam” encompass all types of electromagnetic radiation, including ultraviolet (UV) or deep ultraviolet (DUV) radiation (e.g. having a wavelength of 365, 248, 193, 157 or 126 nm) and extreme ultra-violet (EUV) radiation (e.g. having a wavelength in the range of 5-20 nm), as well as particle beams, such as ion beams or electron beams.

[0050] Various patterns on or provided by a patterning device may have different process windows, i.e., a space of processing variables under which a pattern will be produced within specification. Examples of pattern specifications that relate to potential systematic defects include checks for necking, line pull back, line thinning, critical dimension (CD), edge placement, overlapping, resist top loss, resist undercut and / or bridging. The process window of the patterns on a patterning device or an area thereof may be obtained by merging (e.g., overlapping) process windows of each individual pattern. The boundary of the process window of a group of patterns comprises boundaries of process windows of some of the individual patterns. In other words, these individual patterns limit the process window of the group of patterns. These patterns can be referred to as “hotspots” or “process window limiting patterns (PWLPs),” which are used interchangeably herein. When controlling a part of a patterning process, it is possible and economical to focus on the hot spots. When the hot spots are not defective, it is most likely that other patterns are not defective.

[0051] As shown in Fig. 2, the lithography apparatus LA may form part of a lithographic cell LC, also sometimes referred to a lithocell or cluster, which also includes apparatuses to perform pre- and post-exposure processes on a substrate. Conventionally these include one or more spin coaters SC to deposit one or more resist layers, one or more developers to develop exposed resist, one or more chill plates CH and / or one or more bake plates BK. A substrate handler, or robot, RO picks up one or more substrates from input / output port I / Ol, I / O2, moves them between the different process apparatuses and delivers them to the loading bay LB of the lithography apparatus. These apparatuses, which are often collectively referred to as the track, are under the control of a track control unit TCU which is itself controlled by the supervisory control system SCS, which also controls the lithography apparatus via lithography control unit LACU. Thus, the different apparatuses can be operated to maximize throughput and processing efficiency.

[0052] In order that a substrate that is exposed by the lithography apparatus is exposed correctly and consistently and / or in order to monitor a part of the patterning process (e.g., a device manufacturing process) that includes at least one pattern transfer step (e.g., an optical lithography step), it is desirable to inspect a substrate or other object to measure or determine one or more properties such as alignment, overlay (which can be, for example, between structures in overlying layers or between structures in a same layer that have been provided separately to the layer by, for example, a double patterning process), line thickness, critical dimension (CD), focus offset, a material property, etc. For example, contamination on reticle clamp membranes (e.g., as described herein) may adversely affect overlay because clamping a reticle over such contamination will distort the reticle. Accordingly, a manufacturing facility in which lithocell LC is located also typically includes a metrology system that measures some or all of the substrates W (Fig. 1) that have been processed in the lithocell or other objects in the lithocell. The metrology system may be part of the lithocell LC, for example it may be part of the lithography apparatus LA (such as alignment sensor AS (Fig. 1)).

[0053] The one or more measured parameters may include, for example, alignment, overlay between successive layers formed in or on the patterned substrate, critical dimension (CD) (e.g., critical linewidth) of, for example, features formed in or on the patterned substrate, focus or focus error of an optical lithography step, dose or dose error of an optical lithography step, optical aberrations of an optical lithography step, etc. This measurement may be performed on a target of the product substrate itself and / or on a dedicated metrology target provided on the substrate. The measurement can be performed after-development of a resist but before etching, after-etching, after deposition, and / or at other times.

[0054] There are various techniques for making measurements of the structures formed in the patterning process, including the use of a scanning electron microscope, an image-based measurementtool and / or various specialized tools. As discussed above, a fast and non-invasive form of specialized metrology tool is one in which a beam of radiation is directed onto a target on the surface of the substrate and properties of the scattered (diffracted / reflected) beam are measured. By evaluating one or more properties of the radiation scattered by the substrate, one or more properties of the substrate can be determined. This may be termed diffraction-based metrology. One such application of this diffraction-based metrology is in the measurement of feature asymmetry within a target. This can be used as a measure of overlay, for example, but other applications are also known. For example, asymmetry can be measured by comparing opposite parts of the diffraction spectrum (for example, comparing the -1st and +lstorders in the diffraction spectrum of a periodic grating). Another application of diffraction-based metrology is in the measurement of feature width (CD) within a target.

[0055] Metrology results may be provided directly or indirectly to the supervisory control system SCS. If an error is detected, an adjustment may be made to exposure of a subsequent substrate (especially if the inspection can be done soon and fast enough that one or more other substrates of the batch are still to be exposed) and / or to subsequent exposure of the exposed substrate. Also, an already exposed substrate may be stripped and reworked to improve yield, or discarded, thereby avoiding performing further processing on a substrate known to be faulty. In a case where only some target portions of a substrate are faulty, further exposures may be performed only on those target portions which meet specifications.

[0056] Within a metrology system, a metrology apparatus is used to determine one or more properties of the substrate, and in particular, how one or more properties of different substrates vary, or different layers of the same substrate vary from layer to layer. As noted above, the metrology apparatus may be integrated into the lithography apparatus LA or the lithocell LC or may be a standalone device.

[0057] To enable the metrology, one or more targets can be provided on the substrate. In some embodiments, the target is specially designed and may comprise a periodic structure. In some embodiments, the target is a part of a device pattern, e.g., a periodic structure of the device pattern. In some embodiments, the device pattern is a periodic structure of a memory device (e.g., a Bipolar Transistor (BPT), a Bit Line Contact (BLC), etc. structure).

[0058] In some embodiments, the target on a substrate may comprise one or more 1-D periodic structures (e.g., gratings), which are printed such that after development, the periodic structural features are formed of solid resist lines. In some embodiments, the target may comprise one or more 2-D periodic structures (e.g., gratings), which are printed such that after development, the one or more periodic structures are formed of solid resist pillars or vias in the resist. The bars, pillars, or vias may alternatively be etched into the substrate (e.g., into one or more layers on the substrate).

[0059] As lithography nodes keep shrinking, more and more complicated wafer designs may be implemented. Various tools and / or techniques may be used by designers to ensure complex designsare accurately transferred to physical wafers. These tools and techniques may include mask optimization, source mask optimization (SMO), OPC, design for control, and / or other tools and / or techniques. The present systems, and / or methods may be used as stand-alone tools and / or techniques, and / or or used in conjunction with semiconductor manufacturing processes, to enhance the accurate transfer of complex designs to physical wafers.

[0060] Fig. 3 illustrates additional example portions of a lithography apparatus 300 (e.g., similar to an or the same as lithography apparatus LA shown in Fig. 1). Fig. 3 illustrates a portion of an extreme ultra violet (EUV) lithography apparatus. Fig. 3 illustrates example lithography apparatus components in proximity to a clamp 312 of lithography apparatus 300, including a tool handler 306, and / or other components.

[0061] In some embodiments, tool handler 306 comprises a reticle handler turret gripper, a reticle handler robot gripper (both having associated components for gripping a reticle during transport), and / or other components. The reticle handler robot gripper may, for example, move a reticle from a pod (e.g., after a user places a reticle in the pod and loads the pod into the lithography apparatus). The reticle handler turret gripper may, for example, move a reticle from the reticle handler robot gripper to reticle clamp(s) 312. Lithography apparatus 300 may include various other mechanical components (translation mechanisms, elevation mechanisms, rotational mechanisms, motors, power generation and transmission components, structural components, etc.) configured to facilitate movement and control of reticle 302 through lithography apparatus 300.

[0062] Fig. 4 illustrates another example lithography apparatus 400 (e.g., similar to an or the same as lithography apparatus LA shown in Fig. 1, with components similar to and / or the same as the components of lithography apparatus LA and / or lithography apparatus 300 shown in Fig. 3). A footprint 414 of apparatus 400 is shown in Fig. 4, with a length L400 of lithography apparatus 400 also shown. Lithography apparatus 400 comprises a loading station 404, a reticle handling system 406, and / or other components. Various components of lithography apparatus 400 may be similar to an or the same as corresponding components of lithography apparatus LA shown in Fig. 1, and / or lithography apparatus 300 shown in Fig. 3.

[0063] One or more standards (e.g., SEMI El 17, SEMI S2, etc.) may govern the design and / or location of one or more components of lithography apparatus 400. For example, loading station 404 is configured to receive reticles input into lithography apparatus 400. In lithography apparatus 400, loading station 404 is a permanent part of lithography apparatus 402, located at a location 410 at or near an end of lithography apparatus 400 (corresponding to a patterning device (e.g., reticle) load port 412 (or load ports 412 - two example load ports 412 are shown in Fig. 4). Loading station 404 is inside a footprint 414 of a perimeter 416 of lithography apparatus 400 at location 410 (e.g., according to the requirements of SEMI El 17).

[0064] In lithography apparatus 400, a reticle in an inner pod and an outer pod may be loaded into loading station 404. Reticle handling system 406 includes a first portion 450 configured to move areticle from loading station 404 to a load port 412, an arm based robot 411 configured to move the reticle from the load port, and / or other portions configured to move the reticle to a patterning device holder 422 such as a reticle stage. Distance 420 from load port(s) 412 to patterning device holder 422 in lithography apparatus 400 spans across arm based robot 411. Distance 420 often varies in lithography apparatuses of different configurations (e.g., associated with different NA’s). Reticle handling system 406 and loading station 404 are typically designed after configuration the design of lithography related portions 480 of lithography apparatus 400 are complete, which means that designs for reticle handling system 406 and loading station 404 often vary apparatus to apparatus (while still complying with the various required standards).

[0065] Fig. 5 illustrates a lithography system 500. Lithography system 500 comprises a lithography apparatus 502, a moveable loading station 504, a handling system 506, and / or other components. Lithography apparatus 502 may be an EUV apparatus, for example. Various components of lithography apparatus 502 may be similar to an or the same as corresponding components of lithography apparatus LA shown in Fig. 1, lithography apparatus 300 shown in Fig. 3, and / or lithography apparatus 400 shown in Fig. 4. However, in system 500, loading station 504 is configured to move 508 relative to lithography apparatus 502, and be coupled with lithography apparatus 502 at a location 510 corresponding to a patterning device (e.g., reticle) load port 512 (or load ports 512 - two example load ports 512 are shown in Fig. 5). Loading station 504 is modular and configured to be moveably coupled with lithography apparatus 502 outside a footprint 514 of a perimeter 516 of lithography apparatus 502 at location 510 corresponding to load port(s) 512 to accommodate different configurations of lithography apparatus 502, and to facilitate maintenance of a common separation distance 520 between load port(s) 512 and a patterning device holder 522 (e.g., a reticle stage) across the different configurations. The different configurations may correspond to different numerical apertures (NA) associated with the lithography apparatus, for example. These NA’s may include 0.33, 0.55, 0.75, and / or other NA’s, for example. (Note that the moveable modularity of loading station 504 may contradict one of more of the required lithography apparatus design standards mentioned above.)

[0066] The moveable modularity of loading station 504 facilitates a reduced footprint 514 and / or volume (e.g., coming out of the page in Fig. 5) of lithography apparatus 502 compared to one or more footprints of prior lithography apparatuses (e.g., footprint 414 of apparatus 400 shown in Fig. 4). For example, as shown in Fig. 5 compared to Fig. 4, the length L500 of a side of system 500 is less than a corresponding length L400 of lithography apparatus 400 (e.g., L500 « L400). Length L500 may be less than length L400 by up to about 250mm, 500mm, 750mm, 1000mm, or more, for example.

[0067] As described herein, lithography apparatus 502 is configured to transfer a pattern from a patterning device 530 (also see mask MA in Fig. 1) to a substrate (not shown in Fig. 5, but see example substrate W in Fig. 1). In some embodiments, lithography apparatus 502 comprises an EUV scanner, patterning device 530 comprises a reticle, and the substrate comprises a wafer, for example.Lithography apparatus 502 is configured to receive the substrate, which has a photoresist layer (e.g., as described with respect to Fig. 2 above). Lithography apparatus 502 is configured to direct radiation from a radiation source (see Fig. 1) toward the substrate via patterning device 530 (once inserted into lithography apparatus 502) to transfer the pattern from patterning device 530 onto the photoresist layer; and facilitate removal a portion of the photoresist layer to form the pattern over the substrate, to form one or more integrated circuits or chips in or on the substrate (e.g., see Fig. 1 and Fig. 2).

[0068] As described above, loading station 504 is configured to be removably coupled with lithography apparatus 502 at location 510, corresponding to load port(s) 512. In some embodiments, loading station 504 may comprise a sheet metal type design like a tool box (e.g., square with wheels). Loading station 504 is configured to receive one or more patterning devices 530 for movement to load port(s) 512. Movement 508 of loading station 504 may be performed manually by a user, automatically (e.g., controlled by one or more processors), and / or in other ways. In some embodiments, loading station 504 comprises wheels, one or more rails, a track, a retractable shelf, and / or other components configured to facilitate movement relative to lithography apparatus 502. Loading station 504 may have an input configured to receive reticles from a user and / or a manual insertion system, one or more storage locations such as slots, an output so that reticles can be moved out of loading station 504 by handling system 506 (as described herein), and / or other components. In some embodiments, loading station 504 may have a rectangular cross section, be made of relatively light weight materials to enhance portability, and / or any have any other characteristics that allow it to function as described.

[0069] In some embodiments, a patterning device 530 is held within an inner pod 532 and an outer pod 534 in loading station 504. One or more of these patterning device / inner pod / outer pod combinations may be in loading station 504 at a given time. Loading station 504 is configured to accept an outer pod 534, which may include one or more features defining how the pod is held. For example, the bottom of a pod door may have a semi mechanical interface, with pins for registration of the pod. The perimeter of a pod may have lead-ins and / or other features, which help the operator place the pod into position. There may also be one or more sensors which sense pod presence and whether a pod is placed properly. Loading station 504 may comprise an electrical connection so that the sensors can be connected to machine logic. Fig. 5 provides an example inset view 580 of a user 582 loading an outer pod 534 into loading station 504. As shown in view 580, various features 590 (e.g., guiding surfaces, registration pins, pin holes, etc., on loading station 504, outer pod 534, or both) may be used to help user 582 properly load outer pod 534 into loading station 504.

[0070] In some embodiments, the removable coupling of loading station 504 is configured to have repeatable accuracy for connection to lithography apparatus 502 (e.g., plus or minus about 5mm (as one possibility) relative to the mechanism which will pick up the pod (e.g., as described herein). The repeatably accurate removable coupling may comprise a docking station to main machine covers of lithography apparatus 502, for example, and / or other components.

[0071] In some embodiments, lithography system 500 comprises a handling system 506. Handling system 506 may comprise a first handler 550 configured to move a patterning device 530 from loading station 504 to a load port 512, and a second handler 552 configured to move the patterning device 530 from load port 512 to holder 522. In some embodiments, second handler 552 may move a patterning device 530 after head 562 moves patterning device 530 from load port 512 to a load lock 598. First handler 550 is configured to move outer pod 534 to a load port 512, and second handler 552 is configured to move patterning device 530 from inner pod 532 at load port 512 to holder 522.

[0072] In some embodiments, first handler 550 comprises a cartesian robot. In some embodiments, first handler 550 comprises a pick and place robot. In some embodiments, first handler 550 comprises an overhead hoist transport. First handler 550 may comprise some combination of any of these, and / or other mechanisms. In some embodiments, first handler 550 comprises one or more rails 560 configured to facilitate movement of patterning device 530 from loading station 504 to a load port 512 in one or more dimensions. For example, Fig. 5 illustrates first handler 550 as a cartesian or pick and place robot that moves 564 along first and second rails. In this example, the first and second rails comprise a linear rail oriented in an x or y dimension relative to the lithography apparatus (x in this example), and a z-rail oriented in a z dimension (in and out of the page in Fig. 5) relative to lithography apparatus 502, respectively. First handler 550 also comprises a head 562 configured to move 566 in the y direction in this example (toward and away from load ports 512), and rotate 568 (e.g., around the z axis) as needed. First handler 550 may include various motors, actuators, bearings, guides, tracks, controllers, processors, sensors, structural components, clips, clamps, and / or other grippers, and / or any other hardware and / or software components needed to facilitate the functionality described herein.

[0073] Hardware of handling system 506 can be substantially the same across different configurations of lithography apparatuses 502 (e.g., corresponding to different NA’s) because the modular and moveably coupled loading station 504 facilitates maintenance of separation distance 520 between load port(s) 512 and holder 522 across different configurations of lithography apparatus 502. For example, in some embodiments, the modular and movably coupled loading station 504 is configured to reduce or eliminate a need for a selective compliance assembly robot arm (SC ARA) such as arm based robot 411 shown in Fig. 4, or the reticle handler robot gripper described above with respect to Fig. 3, in first handler 550.

[0074] In this example, distance 520 between loading station 504 and the load port is reduced compared to a corresponding distance in prior lithography apparatuses. Comparing Fig. 5, to Fig. 4, distance 420 in lithography apparatus 400 shown in Fig. 4, spans across arm based robot 411. Arm based robot 411 is not needed at all in lithography apparatus 502 because loading station 504 can be moved (e.g., via wheels or some other mechanism) to any convenient location where a load port 512 is designed into lithography apparatus 502. In this example, loading station 504 is coupled at location 510, right at, or at least proximate to, load port(s) 512 (instead of at the far end of lithographyapparatus 400 where loading station 404 is a permanent part of lithography apparatus 400). Because loading station 504 can be moved, distance 520 from load port(s) 512 can be substantially the same for any configuration of lithography apparatus 502. In other words, load port(s) 512 and patterning device holder 522 (e.g., a reticle stage) can be moved together left or right - in this example image of a lithography apparatus (e.g., 502), with distance 520 being kept the same wherever they are moved. Since loading station 504 is coupled at location 510, arm based robot 411 from lithography apparatus 400 shown in Fig. 4, and / or the reticle handler robot gripper mentioned above with respect to Fig. 3, is not needed to move a reticle from a load port 412. Instead, a relatively simply (compared to arm based robot 411 in lithography apparatus 400 and the reticle handler robot gripper in lithography apparatus 300) pick and place robot can be used.

[0075] Fig. 6 illustrates another view of lithography system 500, including lithography apparatus 502, loading station 504, handing system 506 (including first handler 550), and / or other components. In Fig. 6, system 500 is shown in an x-z orientation (compared to the x-y orientation shown in Fig. 5). Loading station 504 is configured to move relative to lithography apparatus 502, and be coupled with lithography apparatus 502 at a location 510 corresponding to a patterning device (e.g., reticle) load port 512 (or load ports 512 - two example load ports 512 are shown in Fig. 6). As shown in Fig. 6, in some embodiments, first handler 550 comprises one or more rails 560 configured to facilitate movement of a patterning device from loading station 504 to a load port 512 in one or more dimensions. For example, first handler 550 may comprise an overhead hoist transport 600 with a telescoping linear x rail 602. Rail 602 may telescope out, and over loading station 504, such that one or more components 606 (e.g., wires, cables, a platform, etc.) of an overhead hoist mechanism may retrieve (moving 604 in the z direction in this example) a reticle from loading station 504. In some embodiments, One or more sensors, actuators, controllers, etc., may be used to control any of these movements. Loading station 504 can be rolled 610 (in this example) away and stored in a designated location 612 for each lithography apparatus (NA) configuration. Only one such loading station 504 is needed for a plurality of lithography apparatuses 502 (e.g., which may be in proximity to each other).

[0076] As another example, Fig. 7 illustrates another view of a possible embodiment of a portion of lithography system 500, including lithography apparatus 502, loading station 504, handing system 506 (including first handler 550), and / or other components. In Fig. 7, system 500 is shown in a perspective view. As shown in Fig. 7, first handler 550 may comprise one or more rails 560 (e.g., a telescoping linear x rail 602) configured to facilitate movement of a patterning device 700 (loaded by a user 702 in this example) from loading station 504 to a load port 512 in one or more dimensions. In this example, loading station 504 comprises a flip down shelf 710 which comes out of a machine enclosure 712. Shelf 710 may fold back into machine enclosure 712 when not in use, for example. In this embodiment, machine covers may be different for each machine platform to accommodate different locations of loading station 504. Since the machine covers are generally not critical to a main lithography machine, this is acceptable. Note that this configuration (the flip down shelf) mayhave components similar and / or the same as those described above for guiding the user to load an outer pod, registering correctly, sensing whether an outer pod had been loaded correctly, etc.

[0077] Fig. 8 illustrates maintenance of common separation distance 520 between load port(s) 512 and patterning device holder(s) 522 (e.g., reticle stages) across different configurations 800, 802, and 804 of lithography apparatuses 502. The different configurations correspond to different numerical apertures (NA’s) in this example. These NA’s may include 0.33 (configuration 800), 0.55 (configuration 802), 0.75 (configuration 804), and / or other NA’s, for example. Fig. 8 compares different configurations 800 - 804 for lithography apparatus 400 shown in Fig. 4 to corresponding configurations 800 - 804 for lithography apparatus 502 shown in Fig. 5. As described above, loading station 404 is fixed for lithography apparatus 400, while loading station 504 is modular and moveable relative to lithography apparatus 502.

[0078] Lithography apparatus 502 and loading station 504 (together comprising lithography system 500 shown in Fig. 5 — 7) together comprise a layout which contradicts, or finds a loophole in, SEMI El 17 requirements for lithography apparatuses (typically one must follow El 17 when defining the layout of a lithography apparatus). Currently, a manual pod loading station 404 is defined in SEMI El 17 to be inside an apparatus perimeter as shown on the left side of Fig. 8 (also see Fig. 4 above). This requirement, together with different requirements for different configurations of lithography apparatuses (e.g., related to different NA’s), require variable delivery trajectories 810 and distances 812 for a reticle handling system. This drives drastically different hardware solutions for different apparatus configurations 800-804, as described above.

[0079] System 500 (also see Fig. 5-7) provides a modular moveable loading station 504 outside the perimeter footprint of a lithography apparatus 502. This change facilitates flexible positioning of loading station 504 along the length of a lithography apparatus 502, and provides a constant dimension or distance 520 for the reticle trajectory regardless of the lithography apparatus 502 configuration. This facilitates a common and flexible reticle handling system (see system 506 described above) architecture across configurations, among other advantages.

[0080] Fig. 9 illustrates a lithography method 900. In some embodiments, one or more operations of method 900 may be controlled by one or more processors and / or a computing system, as described below (see Fig. 10). The operations of method 900 presented below are intended to be illustrative. In some embodiments, method 900 may be accomplished with one or more additional operations not described, and / or without one or more of the operations discussed. Additionally, the order in which the operations of method 900 are illustrated in Fig. 9 and described below is not intended to be limiting.

[0081] In some embodiments, one or more operations of method 900 may be implemented in and / or controlled by one or more processing devices (e.g., a digital processor, an analog processor, a digital circuit designed to process information, an analog circuit designed to process information, a state machine, and / or other mechanisms for electronically processing information, as described withrespect to Fig. 10 below). The one or more processing devices may include one or more devices executing some or all of the operations of method 900 in response to instructions stored electronically on an electronic storage medium. The one or more processing devices may include one or more devices configured through hardware, firmware, and / or software to be specifically designed for execution of one or more of the operations of method 900 (e.g., see discussion related to Fig. 10 below). For example, the one or more processing devices may run software configured to control a handling system to move a patterning device from a loading station to a holder of a lithography apparatus, control lithography operations, and / or perform other operations.

[0082] At an operation 902, a moveable loading station is moved relative to a lithography apparatus. The moveable loading station may be similar to and / or the same as moveable loading station 504 shown in Fig. 5, for example. The lithography apparatus may be similar to and / or the same as lithography apparatus 502 shown in Fig. 5. Movement of the loading station may be performed manually by a user, automatically (e.g., controlled by one or more processors), and / or in other ways. For example, in some embodiments, operation 902 comprises receiving entry and / or selection of control commands from a user via a user interface (see Fig. 10). The control commands may comprise instructions for moving the loading station, and / or other control commands.

[0083] As described herein, the lithography apparatus is configured to transfer a pattern from a patterning device to a substrate. In some embodiments, the lithography apparatus comprises an extreme ultra violet (EUV) scanner, and the patterning device comprises a reticle, for example. The lithography apparatus is configured to receive the substrate, which has a photoresist layer (e.g., as described with respect to Fig. 2 above). The lithography apparatus is configured to direct radiation from a radiation source toward the substrate via the patterning device to transfer the pattern from the patterning device onto the photoresist layer; and facilitate removal a portion of the photoresist layer to form the pattern over the substrate, to form one or more integrated circuits or chips in or on the substrate (e.g., see Fig. 1 and Fig. 2).

[0084] The lithography apparatus comprises a patterning device load port and / or other components. In some embodiments, the lithography apparatus comprises a holder configured to hold the patterning device during patterning, there being a separation distance between the load port and the holder. The holder may comprise a reticle stage of the lithography apparatus, for example.

[0085] At an operation 904, the loading station is coupled with the lithography apparatus at a location corresponding to the load port. The loading station is configured to receive the patterning device for movement to the load port. In some embodiments, the moveable loading station comprises wheels, one or more rails, a track, a retractable shelf, and / or other components configured to facilitate movement of the moveable loading station relative to the lithography apparatus.

[0086] In some embodiments, the loading station is modular and configured to be moveably coupled with the lithography apparatus outside a footprint of a perimeter of the lithography apparatus at the location corresponding to the load port to accommodate different configurations of thelithography apparatus, and to facilitate maintenance of the separation distance between the load port and the holder across the different configurations. The different configurations may correspond to different numerical apertures (NA) associated with the lithography apparatus, for example.

[0087] In some embodiments, the lithography system comprises a handling system (e.g., similar to and / or the same as handling system 506 shown in Fig. 5). The handling system comprises a first handler configured to move the patterning device from the loading station to the load port, and a second handler configured to move the patterning device from the load port to the holder. In some embodiments, the patterning device is held within an inner pod and an outer pod in the loading station. The first handler is configured to move the outer pod to the load port, and the second handler is configured to move the patterning device from the inner pod at the load port to the holder. These movements may comprise one or more additional operations of method 900.

[0088] Hardware of the handling system is substantially the same across different configurations of lithography apparatuses because the modular and moveably coupled loading station facilitates maintenance of the separation distance between the load port and the holder across different configurations of the lithography apparatus.

[0089] In some embodiments, the first handler comprises a cartesian robot. In some embodiments, the first handler comprises a pick and place robot. In some embodiments, the first handler comprises an overhead hoist transport. In some embodiments, the first handler comprises first and second rails configured to facilitate movement of the patterning device from the loading station to the load port in two dimensions. The first and second rails may comprise a linear rail oriented in an x or y dimension relative to the lithography apparatus, and a z-rail oriented in a z dimension relative to the lithography apparatus, respectively, for example.

[0090] In some embodiments, the modular and movably coupled loading station is configured to reduce or eliminate a need for a selective compliance assembly robot arm (SCARA) in the first handler because a distance between the loading station and the load port is reduced compared to a corresponding distance in prior lithography apparatuses.

[0091] In some embodiments the loading station is modular and configured to be moveably coupled with the lithography apparatus to facilitate a reduced footprint and / or volume of the lithography apparatus compared to one or more footprints of prior lithography apparatuses.

[0092] Fig. 10 is a block diagram that illustrates a computer system 1000 that can assist in implementing the methods, flows, or the systems disclosed herein. Computer system 1000 may be included in and / or electronically coupled to a lithography apparatus (e.g., lithography apparatus 502 shown in Fig. 5), a moveable loading station (e.g., moveable loading station 504 shown in Fig. 5), a handling system (e.g., handling system 506 shown in Fig. 5), and / or other components. Computer system 1000 includes a bus 1002 or other communication mechanism for communicating information, and a processor 1004 (or multiple processors 1004, 1005, etc.) coupled with bus 1002 for processing information. Computer system 1000 also includes a main memory 1006, such as a random accessmemory (RAM) or other dynamic storage device, coupled to bus 1002 for storing information and instructions to be executed by processor 1004. Main memory 1006 also may be used for storing temporary variables or other intermediate information during execution of instructions to be executed by processor 1004. Computer system 1000 further includes a read only memory (ROM) 1008 or other static storage device coupled to bus 1002 for storing static information and instructions for processor 1004. A storage device 1010, such as a magnetic disk or optical disk, is provided and coupled to bus 1002 for storing information and instructions.

[0093] Computer system 1000 may be coupled via bus 1002 to a display 1012, such as a flat panel or touch panel display for displaying information to a computer user. An input device 1014, including alphanumeric and other keys, is coupled to bus 1002 for communicating information and command selections to processor 1004. Another type of user input device is cursor control 1016, such as a mouse, a trackball, or cursor direction keys for communicating direction information and command selections to processor 1004 and for controlling cursor movement on display 1012. This input device typically has two degrees of freedom in two axes, a first axis (e.g., x) and a second axis (e.g., y), that allows the device to specify positions in a plane. A touch panel (screen) display may also be used as an input device.

[0094] In some embodiments, portions of one or more flows and / or methods described herein may be performed by computer system 1000 in response to processor 1004 executing one or more sequences of one or more instructions contained in main memory 1006. Such instructions may be read into main memory 1006 from another computer-readable medium, such as storage device 1010. Execution of the sequences of instructions contained in main memory 1006 causes processor 1004 to perform the flows and / or process steps described herein. One or more processors in a multi-processing arrangement may also be employed to execute the sequences of instructions contained in main memory 1006. In an alternative embodiment, hard-wired circuitry may be used in place of or in combination with software instructions. Thus, the description herein is not limited to any specific combination of hardware circuitry and software.

[0095] The term “computer-readable medium” or “machine readable medium” as used herein refers to any medium that participates in providing instructions to processor 1004 for execution. Such a medium may take many forms, including but not limited to, non-volatile media, volatile media, and transmission media. Non-volatile media include, for example, optical or magnetic disks, such as storage device 1010. Volatile media include dynamic memory, such as main memory 1006. Transmission media include coaxial cables, copper wire and fiber optics, including the wires that comprise bus 1002. Transmission media can also take the form of acoustic or light waves, such as those generated during radio frequency (RF) and infrared (IR) data communications. Common forms of computer-readable media include, for example, a floppy disk, a flexible disk, hard disk, magnetic tape, any other magnetic medium, a CD-ROM, DVD, any other optical medium, punch cards, paper tape, any other physical medium with patterns of holes, a RAM, a PROM, and EPROM, a FLASH-EPROM, any other memory chip or cartridge, a carrier wave as described hereinafter, or any other medium from which a computer can read.

[0096] Various forms of computer readable media may be involved in carrying one or more sequences of one or more instructions to processor 1004 for execution. For example, the instructions may initially be borne on a magnetic disk of a remote computer. The remote computer can load the instructions into its dynamic memory and send the instructions over a network such as the internet. Bus 1002 can receive the data. Bus 1002 carries the data to main memory 1006, from which processor 1004 retrieves and executes the instructions. The instructions received by main memory 1006 may optionally be stored on storage device 1010 either before or after execution by processor 1004.

[0097] Computer system 1000 may also include a communication interface 1018 coupled to bus 1002. Communication interface 1018 provides a two-way data communication coupling to a network link 1020 that is connected to a local network 1022. Wired and / or wireless links may be implemented. In any such implementation, communication interface 1018 sends and receives electrical, electromagnetic, or optical signals that carry digital data streams representing various types of information.

[0098] Network link 1020 typically provides data communication through one or more networks to other data devices. For example, network link 1020 may provide a connection through local network 1022 to a host computer 1024 or to data equipment operated by an Internet Service Provider (ISP) 1026. ISP 1026 in turn provides data communication services through the worldwide packet data communication network, now commonly referred to as the “Internet” 1028. Local network 1022 and Internet 1028 both use electrical, electromagnetic, or optical signals that carry digital data streams. The signals through the various networks and the signals on network link 1020 and through communication interface 1018, which carry the digital data to and from computer system 1000, are exemplary forms of carrier waves transporting the information.

[0099] Computer system 1000 can send messages and receive data, including program code, through the network(s), network link 1020, and communication interface 1018. In the Internet example, a server 1030 might transmit a requested code for an application program through Internet 1028, ISP 1026, local network 1022 and communication interface 1018. One such downloaded application may provide all or part of a method described herein, for example. The received code may be executed by processor 1004 as it is received, and / or stored in storage device 1010, or other nonvolatile storage for later execution. In this manner, computer system 1000 may obtain application code in the form of a carrier wave.

[0100] Various embodiments of the present systems and methods are disclosed in the subsequent list of numbered clauses:1. A lithography system, comprising: a lithography apparatus configured to transfer a pattern from a patterning device to a substrate, the lithography apparatus comprising a patterning device load port; and a moveable loading station configured to move relative to the lithography apparatus, and becoupled with the lithography apparatus at a location corresponding to the load port, the loading station configured to receive the patterning device for movement to the load port.2. The system of clause 1, wherein the lithography apparatus further comprises a holder configured to hold the patterning device during patterning, there being a separation distance between the load port and the holder.3. The system of any of the previous clauses, wherein the loading station is modular and configured to be moveably coupled with the lithography apparatus outside a footprint of a perimeter of the lithography apparatus at the location corresponding to the load port to accommodate different configurations of the lithography apparatus, and to facilitate maintenance of the separation distance between the load port and the holder across the different configurations.4. The system of any of the previous clauses, wherein the different configurations correspond to different numerical apertures (NA) associated with the lithography apparatus.5. The system of any of the previous clauses, further comprising a handling system, the handling system comprising a first handler configured to move the patterning device from the loading station to the load port, and a second handler configured to move the patterning device from the load port to the holder.6. The system of any of the previous clauses, wherein the patterning device is held within an inner pod and an outer pod in the loading station, the first handler is configured to move the outer pod to the load port, and the second handler is configured to move the patterning device from the inner pod at the load port to the holder.7. The system of any of the previous clauses, wherein hardware of the handling system is substantially the same across different configurations of lithography apparatuses because a modular and moveably coupled nature of the loading station facilitates maintenance of the separation distance between the load port and the holder across different configurations of the lithography apparatus.8. The system of any of the previous clauses, where the first handler comprises a cartesian robot.9. The system of any of the previous clauses, wherein the first handler comprises a pick and place robot.10. The system of any of the previous clauses, wherein the first handler comprises first and second rails configured to facilitate movement of the patterning device from the loading station to the load port in two dimensions.11. The system of any of the previous clauses, wherein the first and second rails comprise a linear rail oriented in an x or y dimension relative to the lithography apparatus, and a z-rail oriented in a z dimension relative to the lithography apparatus, respectively.12. The system of any of the previous clauses, wherein the first handler comprises an overhead hoist transport.13. The system of any of the previous clauses, wherein a modular and movably coupled nature of the loading station is configured to reduce or eliminate a need for a selective compliance assembly robotarm (SC ARA) in the first handler because a distance between the loading station and the load port is reduced compared to a corresponding distance in prior lithography apparatuses.14. The system of any of the previous clauses, wherein the holder comprises a reticle stage of the lithography apparatus.15. The system of any of the previous clauses, wherein the lithography apparatus comprises an extreme ultra violet (EUV) scanner.16. The system of any of the previous clauses, wherein the patterning device comprises a reticle.17. The system of any of the previous clauses, wherein the loading station is modular and configured to be moveably coupled with the lithography apparatus to facilitate a reduced footprint of the lithography apparatus compared to one or more footprints of prior lithography apparatuses.18. The system of any of the previous clauses, wherein the loading station is modular and configured to be moveably coupled with the lithography apparatus to facilitate a reduced volume of the lithography apparatus compared to one or more volumes of prior lithography apparatuses.19. The system of any of the previous clauses, wherein the lithography apparatus is configured to receive the substrate, the substrate having a photoresist layer, direct radiation from a radiation source toward the substrate via the patterning device to transfer the pattern from the patterning device onto the photoresist layer; and facilitate removal a portion of the photoresist layer to form the pattern over the substrate, to form one or more integrated circuits or chips in or on the substrate.20. The system of any of the previous clauses, wherein the moveable loading station comprises wheels, one or more rails, a track, and / or a retractable shelf configured to facilitate movement of the moveable loading station relative to the lithography apparatus.21. A lithography method, comprising: moving a moveable loading station relative to a lithography apparatus, the lithography apparatus configured to transfer a pattern from a patterning device to a substrate, the lithography apparatus comprising a patterning device load port; and coupling the loading station with the lithography apparatus at a location corresponding to the load port, the loading station configured to receive the patterning device for movement to the load port.22. The method of clause 21, further comprising holding, with a holder of the lithography apparatus, the patterning device during patterning, there being a separation distance between the load port and the holder.23. The method of any of the previous clauses, wherein the loading station is modular and configured to be moveably coupled with the lithography apparatus outside a footprint of a perimeter of the lithography apparatus at the location corresponding to the load port to accommodate different configurations of the lithography apparatus, and to facilitate maintenance of the separation distance between the load port and the holder across the different configurations.24. The method of any of the previous clauses, wherein the different configurations correspond to different numerical apertures (NA) associated with the lithography apparatus.25. The method of any of the previous clauses, further comprising moving the patterning device fromthe loading station to the holder with a handling system, the handling system comprising a first handler configured to move the patterning device from the loading station to the load port, and a second handler configured to move the patterning device from the load port to the holder.26. The method of any of the previous clauses, wherein the patterning device is held within an inner pod and an outer pod in the loading station, the first handler is configured to move the outer pod to the load port, and the second handler is configured to move the patterning device from the inner pod at the load port to the holder.27. The method of any of the previous clauses, wherein hardware of the handling system is substantially the same across different configurations of lithography apparatuses because a modular and moveably coupled nature of the loading station facilitates maintenance of the separation distance between the load port and the holder across different configurations of the lithography apparatus.28. The method of any of the previous clauses, where the first handler comprises a cartesian robot.29. The method of any of the previous clauses, wherein the first handler comprises a pick and place robot.30. The method of any of the previous clauses, wherein the first handler comprises first and second rails configured to facilitate movement of the patterning device from the loading station to the load port in two dimensions.31. The method of any of the previous clauses, wherein the first and second rails comprise a linear rail oriented in an x or y dimension relative to the lithography apparatus, and a z-rail oriented in a z dimension relative to the lithography apparatus, respectively.32. The method of any of any of the previous clauses, wherein the first handler comprises an overhead hoist transport.33. The method of any of any of the previous clauses, wherein a modular and movably coupled nature of the loading station is configured to reduce or eliminate a need for a selective compliance assembly robot arm (SC ARA) in the first handler because a distance between the loading station and the load port is reduced compared to a corresponding distance in prior lithography apparatuses.34. The method of any of any of the previous clauses, wherein the holder comprises a reticle stage of the lithography apparatus.35. The method of any of any of the previous clauses, wherein the lithography apparatus comprises an extreme ultra violet (EUV) scanner.36. The method of any of any of the previous clauses, wherein the patterning device comprises a reticle.37. The method of any of any of the previous clauses, wherein the loading station is modular and configured to be moveably coupled with the lithography apparatus to facilitate a reduced footprint of the lithography apparatus compared to one or more footprints of prior lithography apparatuses.38. The method of any of any of the previous clauses, wherein the loading station is modular and configured to be moveably coupled with the lithography apparatus to facilitate a reduced volume ofthe lithography apparatus compared to one or more volumes of prior lithography apparatuses.39. The method of any of any of the previous clauses, wherein the lithography apparatus is configured to receive the substrate, the substrate having a photoresist layer, direct radiation from a radiation source toward the substrate via the patterning device to transfer the pattern from the patterning device onto the photoresist layer; and facilitate removal a portion of the photoresist layer to form the pattern over the substrate, to form one or more integrated circuits or chips in or on the substrate.40. The method of any of the previous clauses, wherein the moveable loading station comprises wheels, one or more rails, a track, and / or a retractable shelf configured to facilitate movement of the moveable loading station relative to the lithography apparatus.41. A semiconductor device manufacturing method comprising: receiving a substrate with a photoresist layer; directing radiation from a radiation source to transfer a pattern from a patterning device onto the photoresist layer; and removing a portion of the photoresist layer to form the pattern over the substrate; wherein: a lithography apparatus is configured to transfer the pattern from the patterning device to the photoresist layer of the substrate, the lithography apparatus comprising a patterning device load port; and a moveable loading station is configured to move relative to the lithography apparatus, and be coupled with the lithography apparatus at a location corresponding to the load port, the loading station configured to receive the patterning device for movement to the load port.

[0101] The concepts disclosed herein may be associated with any generic imaging system for imaging sub wavelength features, and may be especially useful with emerging imaging technologies capable of producing increasingly shorter wavelengths. Emerging technologies already in use include EUV (extreme ultra violet), DUV lithography that is capable of producing a 193nm wavelength with the use of an ArF laser, and even a 157nm wavelength with the use of a Fluorine laser. Moreover, EUV lithography is capable of producing wavelengths within a range of 20-5nm by using a synchrotron or by hitting a material (either solid or a plasma) with high energy electrons in order to produce photons within this range.

[0102] While the concepts disclosed herein may be used for wafer manufacturing on a substrate such as a silicon wafer, it shall be understood that the disclosed concepts may be used with any type of manufacturing system, e.g., those used for manufacturing on substrates other than silicon wafers. In addition, the combination and sub-combinations of disclosed elements may comprise separate embodiments. For example, the modular moveable loading station, and the handling system may comprise separate embodiments, and / or these features may be used together in the same embodiment.

[0103] The descriptions above are intended to be illustrative, not limiting. Thus, it will be apparent to one skilled in the art that modifications may be made as described without departing from the scope of the claims set out below.

Claims

CLAIMS1. A lithography system, comprising: a lithography apparatus configured to transfer a pattern from a patterning device to a substrate, the lithography apparatus comprising a patterning device load port; and a moveable loading station configured to move relative to the lithography apparatus, and be coupled with the lithography apparatus at a location corresponding to the load port, the loading station configured to receive the patterning device for movement to the load port.

2. The system of claim 1, wherein the lithography apparatus further comprises a holder configured to hold the patterning device during patterning, there being a separation distance between the load port and the holder.

3. The system of claim 1, wherein the loading station is modular and configured to be moveably coupled with the lithography apparatus outside a footprint of a perimeter of the lithography apparatus at the location corresponding to the load port to accommodate different configurations of the lithography apparatus, and to facilitate maintenance of the separation distance between the load port and the holder across the different configurations.

4. The system of claim 1, wherein the different configurations correspond to different numerical apertures (NA) associated with the lithography apparatus.

5. The system of claim 1, further comprising a handling system, the handling system comprising a first handler configured to move the patterning device from the loading station to the load port, and a second handler configured to move the patterning device from the load port to the holder; wherein the patterning device is held within an inner pod and an outer pod in the loading station, the first handler is configured to move the outer pod to the load port, and the second handler is configured to move the patterning device from the inner pod at the load port to the holder; and wherein hardware of the handling system is substantially the same across different configurations of lithography apparatuses because a modular and moveably coupled nature of the loading station facilitates maintenance of the separation distance between the load port and the holder across different configurations of the lithography apparatus.

6. The system of claim 5, wherein the first handler comprises a cartesian robot or a pick and place robot.

7. The system of claim 5, wherein:the first handler comprises first and second rails configured to facilitate movement of the patterning device from the loading station to the load port in two dimensions; and the first and second rails comprise a linear rail oriented in an x or y dimension relative to the lithography apparatus, and a z-rail oriented in a z dimension relative to the lithography apparatus, respectively.

8. The system of claim 5, wherein the first handler comprises an overhead hoist transport.

9. The system of claim 5, wherein: a modular and movably coupled nature of the loading station is configured to reduce or eliminate a need for a selective compliance assembly robot arm (SC ARA) in the first handler because a distance between the loading station and the load port is reduced compared to a corresponding distance in prior lithography apparatuses; the holder comprises a reticle stage of the lithography apparatus; the lithography apparatus comprises an extreme ultra violet (EUV) scanner; and the patterning device comprises a reticle.

10. The system of claim 1, wherein: the loading station is modular and configured to be moveably coupled with the lithography apparatus to facilitate a reduced footprint of the lithography apparatus compared to one or more footprints of prior lithography apparatuses; or the loading station is modular and configured to be moveably coupled with the lithography apparatus to facilitate a reduced volume of the lithography apparatus compared to one or more volumes of prior lithography apparatuses.

11. The system of claim 1, wherein the lithography apparatus is configured to receive the substrate, the substrate having a photoresist layer, direct radiation from a radiation source toward the substrate via the patterning device to transfer the pattern from the patterning device onto the photoresist layer; and facilitate removal a portion of the photoresist layer to form the pattern over the substrate, to form one or more integrated circuits or chips in or on the substrate.

12. The system of claim 1, wherein the moveable loading station comprises wheels, one or more rails, a track, and / or a retractable shelf configured to facilitate movement of the moveable loading station relative to the lithography apparatus.

13. A lithography method, comprising:moving a moveable loading station relative to a lithography apparatus, the lithography apparatus configured to transfer a pattern from a patterning device to a substrate, the lithography apparatus comprising a patterning device load port; and coupling the loading station with the lithography apparatus at a location corresponding to the load port, the loading station configured to receive the patterning device for movement to the load port.

14. A semiconductor device manufacturing method comprising: receiving a substrate with a photoresist layer; directing radiation from a radiation source to transfer a pattern from a patterning device onto the photoresist layer; and removing a portion of the photoresist layer to form the pattern over the substrate; wherein: a lithography apparatus is configured to transfer the pattern from the patterning device to the photoresist layer of the substrate, the lithography apparatus comprising a patterning device load port; and a moveable loading station is configured to move relative to the lithography apparatus, and be coupled with the lithography apparatus at a location corresponding to the load port, the loading station configured to receive the patterning device for movement to the load port.

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