Systems and methods for inspecting and storing reticles

Abstract

Inspecting and storing reticles within a reticle handler is described. The reticle handler comprises a reticle inspection system and reticle storage. The inspection and storage comprises determining whether a storage location in the reticle storage is available, and determining whether the reticle inspection system is in use. Responsive to determining that the storage location is available and determining that the reticle inspection system is not in use, a reticle is moved for inspection by the reticle inspection system. Responsive to the reticle meeting an inspection requirement, the reticle is moved to the storage location to store the reticle.

Description

SYSTEMS AND METHODS FOR INSPECTING AND STORING RETICLESCROSS-REFERENCE TO RELATED APPLICATION

[0001] This application claims priority of US application 63 / 666,837 which was filed on 02 July, 2024 and which is incorporated herein in its entirety by reference.TECHNICAL FIELD

[0002] This description generally relates to systems and methods for inspecting and storing reticles.BACKGROUND

[0003] A lithography (e.g., projection) apparatus can be used, for example, in the manufacture of integrated circuits (ICs). A patterning device such as a reticle (or mask) may contain or provide a pattern corresponding to an individual layer of the IC (“design layout”). This pattern can be transferred onto a target portion (e.g. comprising one or more dies) of a substrate (e.g., a 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 reticle. In general, a single substrate contains a plurality of adjacent target portions to which the pattern is transferred successively by the lithography apparatus, one target portion at a time. A lithography apparatus may utilize one or more reticles during the manufacture of an IC.SUMMARY

[0004] Inspecting and storing reticles within a reticle handler is described. The reticle handler comprises a reticle inspection system and reticle storage. The inspection and storage comprises determining whether a storage location in the reticle storage is available, and determining whether the reticle inspection system is in use. Responsive to determining that the storage location is available and determining that the reticle inspection system is not in use, a reticle is moved for inspection by the reticle inspection system. Responsive to the reticle meeting an inspection requirement, the reticle is moved to the storage location to store the reticle. Delaying inspection of a reticle until the reticle inspection system is free, and only storing the reticle in the reticle storage if the reticle passes inspection facilitates inspection throughput improvements (e.g., because less movements by the reticle handler are required compared to prior systems), decreases contamination in the reticle storage and / or an associated lithography apparatus, and / or has other advantages.

[0005] According to an embodiment, a method for inspecting and storing reticles within a reticle handler is provided. The reticle handler comprises the reticle inspection system and reticle storage mentioned above, and / or other components. The method comprises determining whether a storage location in the reticle storage is available; and determining whether the reticle inspection system is inuse. Responsive to determining that the storage location is available and determining that the reticle inspection system is not in use, a reticle is moved for inspection by the reticle inspection system. Responsive to the reticle meeting an inspection requirement, the reticle is moved to the storage location to store the reticle.

[0006] In some embodiments, the reticle is identified and moved from a single reticle pod for inspection. The single reticle pod is separate from the reticle handler.

[0007] In some embodiments, the reticle handler comprises a movement arm with a gripper. The movement arm with the gripper is configured to grip the reticle. The movement arm with the gripper is configured to move the reticle from the single reticle pod for inspection. The movement arm with the gripper is configured to move the reticle to the available storage location responsive to the reticle meeting the inspection requirement, or move the reticle back to the single reticle pod responsive to the reticle not meeting the inspection requirement.

[0008] In some embodiments, responsive to determining that the storage location is not available, or determining that the reticle inspection system is in use, the reticle is not moved from the single reticle pod for inspection.

[0009] In some embodiments, the inspection requirement is associated with contamination of the reticle. In some embodiments, moving the reticle to the storage location to store the reticle responsive to the reticle meeting the inspection requirement reduces or prevents contamination of the reticle storage.

[0010] In some embodiments, the reticle handler is associated with a lithography apparatus used for semiconductor manufacturing. The reticle storage may comprise a reticle library for the lithography apparatus, for example. In some embodiments, the lithography apparatus is a deep ultraviolet (DUV) lithography apparatus. In some embodiments, the lithography apparatus is an extreme ultraviolet (EUV) lithography apparatus.

[0011] In some embodiments, initiating reticle inspection and storage responsive to determining that the storage location is available and determining that the reticle inspection system is not in use enhances reticle throughput by reducing necessary movements performed by the reticle handler.

[0012] In some embodiments, the method comprises identifying the reticle based on one or more identifiers coupled to the reticle prior to moving the reticle for inspection. The one or more identifiers may comprise a bar code, a serial number, a radio frequency identification (RFID) tag, and / or other identifiers.

[0013] In some embodiments, the reticle handler comprises one or more processors, and the method further comprises facilitating, with the one or more processors, user enabling or disabling of the available storage location and reticle inspection system use determinations prior to inspection and / or storage of the reticle. The one or more processors facilitate the enabling or disabling by causing display of one or more user instruction entry and / or selection fields via a user interface associated with the reticle handler. The enabling or disabling causes configuration changes in thereticle handler depending on whether a user desires the reticle handler to determine whether the storage location in the reticle storage is available, and determine whether the reticle inspection system is in use, prior to moving the reticle for inspection.

[0014] In some embodiments, the storage location comprises a slot for the reticle in the reticle storage. In some embodiments, the reticle storage comprises up to five, ten, fifteen, twenty, or more slots, each of which potentially comprises an available storage location.

[0015] In some embodiments, the inspection and generating with the inspection system comprises generating image data comprising one or more images of a surface of the reticle from a microscope inspection. The image data may be analyzed for presence of contamination. The reticle may be determined to meet the inspection requirement responsive to an amount of contamination meeting a contamination threshold, for example.

[0016] According to another embodiment, there is provided a system configured to perform one or more operations of the method described above.

[0017] According to another embodiment, there is provided a non-transitory computer readable medium having instructions thereon. The instructions, when executed by a computer, cause the computer to cause, control, and / or perform one or more of the operations of the method described above.BRIEF DESCRIPTION OF THE DRAWINGS

[0018] 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:

[0019] Fig. 1 schematically depicts a lithography apparatus, according to an embodiment.

[0020] Fig. 2 schematically depicts an embodiment of a lithographic cell or cluster, according to an embodiment.

[0021] Fig. 3A illustrates a portion of an extreme ultra violet (EUV) lithographic apparatus, according to an embodiment.

[0022] Fig. 3B illustrates a portion of a deep ultra violet (DUV) lithographic apparatus, according to an embodiment.

[0023] Fig. 3C is an enlarged view of a portion of the lithographic apparatus shown in Fig. 3B, according to an embodiment.

[0024] Fig. 4 illustrates a method for inspecting and storing reticles within a reticle handler, according to an embodiment.

[0025] Fig. 5 illustrates a system for inspecting and storing reticles, according to an embodiment.

[0026] Fig. 6 illustrates a flow diagram for inspecting and storing reticles within a reticle handler,according to an embodiment.

[0027] Fig. 7 is a block diagram of an example computer system, according to an embodiment.DETAILED DESCRIPTION

[0028] In general, a reticle (or mask) may be a transparent block of material that is covered with a pattern defined by a different, opaque material. Or a reticle may be an opaque block of material coated with a patterned mirror, for example. Various reticles are fed into a lithography apparatus and used to form layers of a semiconductor device. The pattern defined on a given reticle corresponds to features produced in one or more layers of the semiconductor device. Often, a plurality of reticles are automatically fed into a lithography apparatus during manufacturing and used to form corresponding layers of a semiconductor device. A clamp in the lithography apparatus is used to secure a reticle during processing. This clamp may become contaminated with particles of material transferred from reticles causing performance degradation over time, and requiring periodic cleaning to restore performance. Cleaning these clamps can require stopping the lithography apparatus and the manufacturing process. This cleaning can require several hours or weeks to complete, may introduce other contaminants into the system, and / or have other disadvantages.

[0029] As described above, the present systems and methods facilitate inspecting and storing reticles within a reticle handler. The present systems and methods delay inspection of a reticle until a reticle inspection system of the reticle handler is free, and only store a reticle if the reticle passes inspection. This facilitates reticle inspection throughput improvements (e.g., because less inspection and storage related movements by the reticle handler are required compared to prior systems), decreases contamination in reticle storage and / or an associated lithography apparatus, reduces a need for cleaning the lithography apparatus (e.g., less frequent cleaning, and / or less intense cleaning may be required), and / or has other advantages.

[0030] Although specific reference may be made in this text to the manufacture of integrated circuits (ICs), it should be understood that the described systems and methods may have many other possible applications. For example, these systems and methods 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.”

[0031] As an introduction, prior to transferring a pattern from a patterning device such as a reticle 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 / orother 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.

[0032] 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 such as a reticle 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.

[0033] 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.

[0034] As semiconductor manufacturing processes continue to advance, the dimensions of functional elements have continually been reduced while the number of functional elements, such as transistors, per device has been steadily increasing over decades, following a trend commonly referred to as “Moore’s law”. At the current state of technology, layers of devices are manufactured using lithography apparatuses that project a design layout onto a substrate using illumination from an extreme ultraviolet (EUV), or a deep-ultraviolet (DUV) illumination source, creating individual functional elements having dimensions well below 100 nm, i.e. less than half the wavelength of the radiation from the illumination source (e.g., a 193 nm illumination source).

[0035] This process in which features with dimensions smaller than the classical resolution limit of a lithographic projection apparatus are printed, is commonly known as low-kl lithography, according to the resolution formula CD = kl / / . / NA. where I is the wavelength of radiation employed (currently in most cases 248nm or 193nm), NA is the numerical aperture of projection optics in the lithographic projection apparatus, CD is the “critical dimension’ -generally the smallest feature size printed-andkl is an empirical resolution factor. In general, the smaller kl the more difficult it becomes to reproduce a pattern on the substrate that resembles the shape and dimensions planned by a designer in order to achieve particular electrical functionality and performance. To overcome these difficulties, sophisticated fine-tuning steps are applied to the lithographic projection apparatus, the design layout, or the reticle. These include, for example, but not limited to, optimization of NA and optical coherence settings, customized illumination schemes, use of phase shifting patterning devices, optical proximity correction (OPC, sometimes also referred to as “optical and process correction”) in the design layout, overlay measurement, or other methods generally defined as “resolution enhancement techniques” (RET).

[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. UV radiation, DUV radiation, or EUV radiation); a support structure (e.g. a mask table) MT constructed to support a patterning device such as a reticle (e.g. a mask) MA and 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 lithographic 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 lithographic 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 be arranged 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. Theintensity 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-inner, 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 support structure MT supports the patterning device (the reticle or mask MA) 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 reticle or mask that can be used to impart a pattern in a target portion of the substrate. In an embodiment, a patterning device is any reticle or mask 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.

[0044] A patterning device (e.g., a reticle or mask) may be transmissive or reflective. Examples of patterning devices include reticles or masks, programmable mirror arrays, and programmable LCD panels. Reticles or masks are well known in lithography, and include mask types such as binary, alternating phase-shift, and attenuated phase-shift, as well as various hybrid mask types. An example of a programmable mirror array employs a matrix arrangement of small mirrors, each of which can be individually tilted to reflect an incoming radiation beam in different directions. The tilted mirrors impart a pattern in a radiation beam, which is reflected by the mirror matrix.

[0045] The term “projection system” used herein should be broadly interpreted as encompassing any type of projection system, including refractive, reflective, catadioptric, magnetic, electromagnetic, and electrostatic optical systems, or any combination thereof, as appropriate for the exposure radiation being used, or for other factors such as the use of an immersion liquid or the use of a vacuum. Any use of the term “projection lens” herein may be considered as synonymous with the more general term “projection system”.

[0046] The projection system PS has an optical transfer function which may be non-uniform, which can affect the pattern imaged on the substrate W. For unpolarized radiation such effects can be fairly well described by two scalar maps, which describe the transmission (apodization) and relative phase (aberration) of radiation exiting the projection system PS as a function of position in a pupil plane thereof. These scalar maps, which may be referred to as the transmission map and the relative phase map, may be expressed as a linear combination of a complete set of basis functions. Aconvenient set is the Zernike polynomials, which form a set of orthogonal polynomials defined on a unit circle. A determination of each scalar map may involve determining the coefficients in such an expansion. Since the Zernike polynomials are orthogonal on the unit circle, the Zernike coefficients may be determined by calculating the inner product of a measured scalar map with each Zernike polynomial in turn and dividing this by the square of the norm of that Zernike polynomial.

[0047] The transmission map and the relative phase map are field and system dependent. That is, in general, each projection system PS will have a different Zernike expansion for each field point (i.e. for each spatial location in its image plane). The relative phase of the projection system PS in its pupil plane may be determined by projecting radiation, for example from a point-like source in an object plane of the projection system PS (i.e. the plane of the patterning device MA), through the projection system PS and using a shearing interferometer to measure a wavefront (i.e. a locus of points with the same phase). A shearing interferometer is a common path interferometer and therefore, advantageously, no secondary reference beam is required to measure the wavefront. The shearing interferometer may comprise a diffraction grating, for example a two dimensional grid, in an image plane of the projection system (i.e. the substrate table WTa or WTb) and a detector arranged to detect an interference pattern in a plane that is conjugate to a pupil plane of the projection system PS. The interference pattern is related to the derivative of the phase of the radiation with respect to a coordinate in the pupil plane in the shearing direction. The detector may comprise an array of sensing elements such as, for example, charge coupled devices (CCDs).

[0048] The projection system PS of a lithography apparatus may not produce visible fringes and therefore the accuracy of the determination of the wavefront can be enhanced using phase stepping techniques such as, for example, moving the diffraction grating. Stepping may be performed in the plane of the diffraction grating and in a direction perpendicular to the scanning direction of the measurement. The stepping range may be one grating period, and at least three (uniformly distributed) phase steps may be used. Thus, for example, three scanning measurements may be performed in the y- direction, each scanning measurement being performed for a different position in the x-direction. This stepping of the diffraction grating effectively transforms phase variations into intensity variations, allowing phase information to be determined. The grating may be stepped in a direction perpendicular to the diffraction grating (z direction) to calibrate the detector.

[0049] The diffraction grating may be sequentially scanned in two perpendicular directions, which may coincide with axes of a co-ordinate system of the projection system PS (x and y) or may be at an angle such as 45 degrees to these axes. Scanning may be performed over an integer number of grating periods, for example one grating period. The scanning averages out phase variation in one direction, allowing phase variation in the other direction to be reconstructed. This allows the wavefront to be determined as a function of both directions.

[0050] The transmission (apodization) of the projection system PS in its pupil plane may be determined by projecting radiation, for example from a point-like source in an object plane of theprojection system PS (i.e. the plane of the patterning device MA), through the projection system PS and measuring the intensity of radiation in a plane that is conjugate to a pupil plane of the projection system PS, using a detector. The same detector as is used to measure the wavefront to determine aberrations may be used.

[0051] 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 selected regions 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.

[0052] The lithographic 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 (reticle) 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.

[0053] The lithography apparatus LA may also be of a type where at least a portion of the substrate may be covered by a liquid having a relatively high refractive index, e.g. water, to fill a space between the projection system and the substrate. An immersion liquid may also be applied to other spaces in the lithographic apparatus, for example, between the patterning device (e.g., reticle) and the projection system. Immersion techniques are well known in the art for increasing the numerical aperture ofprojection systems. The term “immersion” as used herein does not mean that a structure, such as a substrate, must be submerged in liquid, but rather only means that liquid is located between the projection system and the substrate during exposure.

[0054] In operation of the lithography apparatus LA, 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 (reticle or mask) MA with respect to the path of the radiation beam B, e.g. after mechanical retrieval from a mask library (e.g., reticle storage), 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 (reticle or mask) 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.

[0055] The depicted apparatus may be used in at least one of the following modes: 1. 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). The substrate 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. 2. 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. 3. In another mode, the support structure MT is kept essentiallystationary 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.

[0056] 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. The substrate may be processed more than once, for example in order to create a multi-layer IC, so that the term substrate may also refer to a substrate that already includes multiple processed layers.

[0057] The terms “radiation” and “beam” used herein 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.

[0058] Various patterns on or provided by a patterning device (e.g., a reticle or mask) 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 “hot spots” 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.

[0059] 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 / O 1 , 1 / 02, moves them between the different process apparatuses and delivers them to the loading bay LB of the lithographic apparatus. These apparatuses, which areoften 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 lithographic apparatus via lithography control unit LACU. Thus, the different apparatuses can be operated to maximize throughput and processing efficiency.

[0060] In order that a substrate that is exposed by the lithographic 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 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 lithographic apparatus LA (such as alignment sensor AS (Fig. 1)).

[0061] 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.

[0062] 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 measurement tool 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 atarget.

[0063] Thus, in a device fabrication process (e.g., a patterning process, a lithography process, etc.), a substrate or other objects may be subjected to various types of measurement during or after the process. The measurement may determine whether a particular substrate is defective, may establish adjustments to the process and apparatuses used in the process (e.g., aligning two layers on the substrate or aligning the patterning device to the substrate), may measure the performance of the process and the apparatuses, or may be for other purposes. Examples of measurement include optical imaging (e.g., optical microscope), non-imaging optical measurement (e.g., measurement based on diffraction such as the ASML YieldStar metrology tool, the ASML SMASH metrology system), mechanical measurement (e.g., profiling using a stylus, atomic force microscopy (AFM)), and / or non- optical imaging (e.g., scanning electron microscopy (SEM)).

[0064] 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.

[0065] 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 lithographic apparatus LA or the lithocell LC or may be a standalone device.

[0066] 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 an embodiment, the device pattern is a periodic structure of a memory device.

[0067] 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 an embodiment, 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).

[0068] In some embodiments, one of the parameters of interest of a patterning process is overlay. Overlay can be measured using dark field scatterometry in which the zeroth order of diffraction (corresponding to a specular reflection) is blocked, and only higher orders processed. Diffraction-based overlay using dark-field detection of the diffraction orders enables overlay measurements on smaller targets. These targets can be smaller than the illumination spot and may be surrounded by device product structures on a substrate. In some embodiments, multiple targets can be measured in one radiation capture.

[0069] 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 designs are 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.

[0070] 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.

[0071] As described above, the present systems and methods relate to inspecting and storing reticles for use in a lithography apparatus such as lithography apparatus LA shown in Fig. 1. By way of a non-limiting example, Fig. 3 A, Fig. 3B, and Fig. 3C illustrate example portions of lithographic apparatuses 300 (e.g., similar to an or the same as the lithography apparatus shown in Fig. 1). Fig. 3A illustrates a portion of an extreme ultra violet (EUV) lithographic apparatus. Fig. 3B illustrates a portion of a deep ultra violet (DUV) lithographic apparatus. Fig. 3C is an enlarged view of a portion of the lithographic apparatus shown in Fig. 3B.

[0072] Fig. 3 A illustrates example lithographic apparatus components in proximity to a clamp 312 of lithographic apparatus 300 including a reticle handler 306 and / or other components. Fig. 3A illustrates an EUV inner pod (EIP) 305, with reticle 302, and / or other components. In some embodiments, lithographic apparatus 300 can be configured for deep ultraviolet (DUV) lithography with one or more adjustments from what is shown in Fig. 3A.

[0073] Fig. 3B illustrates an example DUV apparatus (e.g., with a clamp 312 of lithographic apparatus 300 in these figures) and various components of lithographic apparatus 300 including a reticle handler 306, reticle chuck 310, reticle clamp(s) 312, and / or other components.

[0074] In some embodiments, reticle handler 306 comprises a reticle handler turret gripper 308, a reticle handler robot gripper 307 (having associated components for gripping a reticle during transport), and / or other components. Reticle handler robot gripper 307 may, for example, move a reticle 302 from a pod 320 (e.g., after a user places a reticle in pod 320). Reticle handler turret gripper 308 may, for example, move a reticle 302 from reticle handler robot gripper 307 to reticle clamp(s) 312. Lithographic apparatus 300 may include various other mechanical components 322 (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 lithographic apparatus 300. For example, lithographic apparatus 300 may include a rapid exchange device (RED), and / or other components.

[0075] Fig. 3C is an enlarged view of a portion of apparatus 300. Fig. 3C shows a reticle 302, reticle handler turret gripper 308, reticle chuck 310, reticle clamp(s) 312, mechanical components 322, reticle handler robot gripper 307, and / or other components. As shown in Fig. 3C, reticle handler turret gripper 308 is configured to move reticle 302 from reticle handler robot gripper 307 to reticle clamp(s) 312. Moving reticle 302 may comprise moving reticle 302 toward or away from the clamp(s) 312 in horizontal, vertical, and / or other directions. Reticle handler turret gripper 308 and / or reticle handler robot gripper 307 may include various motors, translators, rotational components, clamps, clips, power sources, power transmission components, vacuum mechanisms, and / or other components that facilitate the movement of reticle 302.

[0076] Reticle handlers may conduct or otherwise facilitate automated reticle inspection and automatic storage before a reticle is used by a lithography apparatus. Automatic (e.g., rather than manual or partially automatic) inspection and storage enhance process throughput. These throughput improvements occur because reticles are automatically inspected and stored, without a need for external host interaction (e.g., without a need for some kind of manual intervention by a user).

[0077] However, automated reticle inspection is often treated as a separate operation from reticle storage. For example, automated inspection may involve a series of movements by a reticle handler that are completely separate from a different set of movements by the reticle handler for reticle storage (e.g., picking up and putting down a reticle multiple times - from pod to inspection system and back to pod, and then from pod to storage). As another example, automatic reticle inspection and storage operations may be configurable by the user. Sometimes a reticle handler may be configured such that if a reticle inspection system is busy (inspecting another reticle), uninspected and potentially unqualified (reticles that would not have passed inspection had inspection been performed) reticles are simply auto stored to reticle storage, potentially contaminating the reticle storage. Sometimes a reticle handler may be configured such that reticles move to the reticle storage, even if the reticles did not pass inspection, which again may cause contamination and / or other issues. Users may enable or disable these automated reticle inspection and storage features based on manufacturing throughput pressures, available storage space issues, and / or other factors, for example.

[0078] Fig. 4 illustrates a method for inspecting and storing reticles within a reticle handler such as reticle handler 306 shown in Fig. 3A, 3B, and 3C. The reticle handler comprises a reticle inspection system, reticle storage, and / or other components (see Fig. 5 and corresponding description below). In some embodiments, one or more operations of method 400 may be performed and / or controlled by a reticle handler similar to and / or the same as reticle handler 306 shown in Fig. 3 A, 3B, and / or 3C; reticle handler 502 shown in Fig. 5 and described below; one or more processors and / or a computing system, as described below (see Fig. 7); and / or other components. The operations of method 400 presented below are intended to be illustrative. In some embodiments, method 400 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 400 are illustrated inFig. 4 and described below is not intended to be limiting.

[0079] In some embodiments, one or more operations of method 400 may be implemented in and / or controlled by one or more processing devices (e.g., a computer, 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 software, firmware, and / or hardware mechanisms for electronically processing information, as described with respect to Fig. 5, 6, and 7 below). The one or more processing devices may include one or more devices executing some or all of the operations of method 400 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 400 (e.g., see discussion related to Fig. 7 below).

[0080] At an operation 401, a reticle is identified for potential inspection and / or storage. The reticle may be held in or by a single reticle pod, for example. The single reticle pod is separate from the reticle handler. Identification is based on one or more identifiers coupled to and / or otherwise associated with the reticle. The one or more identifiers may include bar codes, serial numbers, radio frequency identification (RFID) tags, labels, and / or other identifiers. The reticle may be configured such that identifiers are visible to a user, the inspection system (see Fig. 5), and / or the lithography apparatus (e.g., lithography apparatus 300 shown in Fig. 3 A, 3B, 3C) so that the reticle can be properly identified, loaded into and received by the inspection system and / or lithography apparatus, and positioned for inspection.

[0081] At an operation 402, a determination is made as to whether a storage location in reticle storage is available. The reticle storage may be a reticle library, for example (see Fig. 5), and / or other reticle storage. The storage location may be a slot and / or other storage locations. The reticle storage may comprise up to five, ten, fifteen, twenty, or more slots, each of which potentially comprises an available storage location. In some embodiments, each storage location may be equipped with a through beam sensor whose output may be used to determine whether a slot is available. Other types of sensors may (also or instead) be used, such as mechanical switches, cameras, etc. The signal from such a sensor may be communicated to a reticle handler (similar to and / or the same as reticle handler 306 shown in Fig. 3 A, 3B, and / or 3C) and / or reticle handler 502 shown in Fig. 5); one or more processors and / or a computing system, as described below (see Fig. 7); and / or other components.

[0082] At an operation 403, a determination is made as to whether a reticle inspection system (e.g., see Fig. 5) is in use. For example, the inspection system may emit an electronic signal when an inspection is ongoing. This signal may be transmitted to the reticle handler (e.g., a processor of the reticle handler) through electronic connections. Note that, some embodiments, operations 402 and 403 may be executed in reverse order, or substantially concurrently.

[0083] At an operation 404, responsive to determining that the storage location is available, and determining that the reticle inspection system is not in use, the reticle identified at operation 401 ismoved (e.g., by a reticle handler comprising a movement arm with a gripper - see Fig. 5) for inspection by the reticle inspection system. In some embodiments, the reticle handler comprises a movement arm with a gripper. The movement arm with the gripper is configured to grip the reticle and move the reticle from the single reticle pod for inspection. Responsive to determining that the storage location is not available, or determining that the reticle inspection system is in use, the reticle is not moved from the single reticle pod for inspection.

[0084] The movement arm and / or the gripper may be operable to perform any combination of x, y, and / or z direction displacement of a reticle; tilting a reticle; rotating a reticle; and / or other movements. The movement arm and / or the gripper may include various mechanical components (translation mechanisms, elevation mechanisms, rotational mechanisms, motors, power generation and transmission components, structural components, etc.) configured to facilitate movement and control of a reticle. For example, the movement arm and / or the gripper may include various motors, translators, rotational components, clamps, clips, power sources, power transmission components, vacuum mechanisms, and / or other components that facilitate the movement of a reticle.

[0085] In some embodiments, operation 404 comprises performing the inspection and generating, with the inspection system, image data comprising one or more images of a surface of the reticle from a microscope inspection, pattern accuracy data, flatness data, and / or other data about a reticle.Operation 404 may also include analyzing the image data for presence of contamination, the pattern accuracy data, the flatness data, and / or the other data, and determining that the reticle meets the inspection requirement. In some embodiments, the reticle may meet the inspection requirement responsive to an amount of contamination meeting a contamination threshold. A primary purpose of the inspection is to determine if contamination is present on a reticle. However, image data can also be analyzed to check if the pellicle (a structure underneath a reticle to prevent particles from directly touch the patterns) is broken, or if a pellicle is too wide, or itself flatness out of specification, for example.

[0086] As an inspection example, image data of a surface of a reticle confirming presence or absence of contamination particles, confirming presence or absence of one or more types of the contamination particles, and / or confirming other information may be generated. In some embodiments, the types of particles may include tantalum contamination particles, chrome contamination particles, and / or other types of contamination particles. In some embodiments, the image data comprises one or more images from a microscope inspection of the surface of a reticle. As another example, flatness of the surface of a reticle may be determined. The flatness may be determined to confirm the presence or absence of contamination particles, for example.

[0087] In some embodiments, a computer system (such as the computer system shown in Fig. 7 and described below) is configured to determine (based on the image data or the flatness in these examples) presence of the contamination particles, and whether a reticle meets a contamination threshold. This may include generating and / or analyzing a contamination particle distribution map forthe surface of the reticle, for example.

[0088] In some embodiments, operation 404 comprises receiving entry and / or selection of control commands from a user via a user interface. The control commands comprise instructions for moving and / or inspecting a certain reticle, or a region of interest on the reticle, and / or other control commands. In some embodiments, the control commands are configured to facilitate fully automated, or semi-automated inspection. Facilitating semi-automated inspection may comprise causing real time or near real time display of one or more images of the surface of a reticle to a user with a user interface (e.g., see user interface 516 described below related to Fig. 5). Facilitating semi-automated inspection may also include receiving entry and / or selection of control commands from the user via the user interface. These control commands may be received in real time or near real time as one or more images are displayed to the user. In some embodiments, the control commands comprise live adjustments, for example.

[0089] The control commands may comprise instructions for moving a reticle, one or more image capture devices, and / or other components based on a region on interest of the reticle, for example. The region of interest may be a certain area of a reticle that appears contaminated in an image, or is typically contaminated (e.g., as determined based on prior inspections), and / or other regions of interest. The control commands may comprise instructions for adjustment of a focus, zoom, or other characteristics of one or more image capture devices. For example, an image capture device may have an electronically controllable focus setting, zoom setting, etc. The control commands may comprise instructions for adjustment of illumination from one or more light sources associated with one or more image capture devices. For example, a light source may have an electronically controllable brightness, wavelength (color), and / or other characteristics. As another example, an image capture device may have an electronically controllable contrast setting. The control commands may comprise instructions for obtaining updated images using an adjusted zoom, focus, and / or illumination, for example, and / or other control commands. In some embodiments, facilitating semiautomated inspection comprises causing display of the updated images to the user with the user interface so that the user can determine presence of contamination in the region of interest (e.g., on a reticle or a specific portion of a reticle) based on the updated images.

[0090] In some embodiments, the control commands facilitate automated inspection. Automated inspection may be performed in real time or near real time as inspection data (e.g., image data, pattern data, flatness data, etc.) is obtained. Automated inspection may also comprise live adjustments, for example. In some embodiments, facilitating automated inspection comprises automatically determining a region of interest for a reticle based on one or more images of the reticle. The region of interest may be a certain predetermined area of a reticle, for example, which appears contaminated in an image, or is typically contaminated (e.g., as determined based on prior inspections), and / or other regions of interest. Facilitating automated inspection comprises controlling the inspection system (see reticle handler 502 and inspection system 506 in Fig. 5) to move the reticle and one or more imagecapture devices and / or other inspection sensors based on the region on a position and / or orientation of the reticle and / or a region of interest on the reticle, and / or other information. In some embodiments, facilitating automated inspection comprises adjusting a zoom and / or focus of one or more image capture devices based on one or more images and / or other information; adjusting illumination from one or more light sources associated with one or more image capture devices based on the one or more images and / or other information, and / or other operations. In some embodiments, facilitating automated inspection comprises causing one or more image capture devices to obtain updated images using an adjusted focus and / or illumination; determining presence of contamination in a region of interest based on the updated images; and / or other operations.

[0091] In some embodiments, the reticle handler is configured to facilitate the automated (or semiautomated) inspection based on a trained machine learning algorithm. The trained machine learning algorithm is configured to receive a reticle identification, image data, pattern data, flatness data, and / or other information as input, and output corresponding control commands. The corresponding control commands may be related to where to move a reticle, determining a region of interest, controlling the movement arm and gripper to move a reticle and one or more image capture devices and / or other sensors, adjusting the zoom and / or focus, adjusting the illumination, causing one or more image capture devices to obtain images, determining presence of contamination, determining whether a reticle satisfies inspection criteria, and / or other commands. In some embodiments, the trained machine learning algorithm may be trained based on previously obtained images of reticles, with and without contamination, as one possible example, and / or other information. In some embodiments, the machine learning algorithm may be and / or include mathematical equations, algorithms, plots, charts, networks (e.g., neural networks), and / or other tools and machine learning components. For example, the machine learning algorithms may be and / or include one or more neural networks having an input layer, an output layer, and one or more intermediate or hidden layers. In some embodiments, the one or more neural networks may be and / or include deep neural networks (e.g., neural networks that have one or more intermediate or hidden layers between the input and output layers).

[0092] At an operation 405, responsive to the reticle meeting an inspection requirement, the reticle is moved to the storage location to store the reticle. If the reticle does not meet the inspection requirement, the reticle is placed back into the pod, or otherwise not placed into reticle storage. For example, the movement arm with the gripper is configured to move the reticle to the available storage location responsive to the reticle meeting the inspection requirement, or move the reticle back to the single reticle pod responsive to the reticle not meeting the inspection requirement. Initiating reticle inspection and storage responsive to determining that the storage location is available and determining that the reticle inspection system is not in use enhances reticle throughput by reducing necessary movements performed by the reticle handler. For example, once gripped by the gripper, the reticle is inspected and potentially stored, without a need for several individual movements associated with inspection (e.g., returning a reticle back to a pod, and then picking it back up again to be moved tostorage), and several additional individual movements associated with storage. In addition, a reticle is not moved at all if the inspection system is occupied.

[0093] In some embodiments, the inspection requirement is associated with contamination of the reticle (e.g., as described in one or more of the examples discussed above). Moving the reticle to the storage location to store the reticle responsive to the reticle meeting the inspection requirement reduces or prevents contamination of the reticle storage. For example, the reticle handler may be associated with a lithography apparatus used for semiconductor manufacturing. The lithography apparatus may be a DUV apparatus, an EUV apparatus, and / or other lithography apparatuses. The reticle storage may comprise a reticle library for the lithography apparatus, such that reducing or preventing contamination of the reticle library reduces or prevents contamination in the lithography apparatus (e.g., at clamps and / or other components of the lithography apparatus). Other advantages are contemplated.

[0094] In some embodiments, the reticle handler comprises one or more processors. The one or more processors may comprise hardware, software, firmware, and / or other components (e.g., as described herein - see Fig. 7). The one or more processors may form and / or be included in a computing system (e.g., as shown in Fig. 7), for example. In additional to other functionality described herein (e.g., see the examples above related to inspection), the one or more processors and / or the computing system may be configured to facilitate user enabling or disabling of the available storage location and reticle inspection system use determinations prior to inspection and / or storage of the reticle. The one or more processors facilitate the enabling or disabling by causing display of one or more user instruction entry and / or selection fields via a user interface (see user interface 516 in Fig. 5) associated with the reticle handler, and / or using other methods. The enabling or disabling causes configuration changes in the reticle handler depending on whether a user desires the reticle handler to determine whether the storage location in the reticle storage is available, and determine whether the reticle inspection system is in use, prior to moving the reticle for inspection.

[0095] Configuration changes may include software, process parameter, and / or other changes.These are provided because each user may have different preferences and / or priorities. For example, a user may prefer that a reticle wait in a pod until inspection system is available because they prioritize cleanliness of storage over pod availability, while another user may prefer allowing a reticle to directly move to storage before it is inspected, so that the pod may be freed to be removed from the system for other use. Configuration changeability may be provided to satisfy both kinds of users.

[0096] Fig. 5 illustrates a system 500 for inspecting and storing reticles. System 500 comprises a reticle handler 502, one or more processors 504, and / or other components. Reticle handler 502 may be similar to and / or the same as reticle handler 306 (Fig. 3A, 3B, 3C), for example. One or more processors 504 may form and / or be included in a computer system such as computer system 700 shown in Fig. 7 and described below, and / or other components. System 500 may be associated with (e.g., part of and / or coupled to) a lithography apparatus 510 (e.g., DUV or EUV). Lithographyapparatus 510 may be similar to and / or the same as lithography apparatuses LA (Fig. 1), and / or 300 (Fig. 3A, 3B, 3C) described above. Reticle handler 502 comprises a reticle inspection system 506, reticle storage 508, a movement arm 512 with a gripper 514 (e.g., which may be similar to and / or the same as reticle handler robot gripper 307 with various mechanical components for translation, elevation, rotation, power generation and transmission, structural components, etc.), a user interface 516, a load port 518, and / or other components.

[0097] One or more processors 504 are configured to determine whether a storage location 520 in reticle storage 508 is available. Storage location 520 may comprise a slot, for example, and / or other storage locations. In some embodiments, reticle storage 508 comprises up to five, ten, fifteen, twenty or more slots, each of which potentially comprises an available storage location 520. One or more processors 504 are also configured to determine whether reticle inspection system 506 is in use. Responsive to determining that a storage location 520 is available, and determining that reticle inspection system 506 is not in use, the one or more processors 504 are configured to cause movement (using movement arm 512 and gripper 514) of a reticle 530 for inspection by reticle inspection system 506. Responsive to reticle 530 meeting an inspection requirement, one or more processors 504 cause movement (again using movement arm 512 and gripper 514) of reticle 530 to a storage location 520 to store reticle 530.

[0098] In system 500, reticle 530 is identified and moved from a single reticle pod 540 for inspection. Reticle handler 502 is configured to identify reticle 530 based on one or more identifiers 550 (e.g., a bar code, a serial number, an RFID tag, etc.) coupled to and / or otherwise associated with reticle 530 prior to moving reticle 530 for inspection. As shown in Fig. 5, single reticle pod 540 is typically separate from reticle handler 502. One or more processors 504 are configured to move reticle 530 back to single reticle pod 540 responsive to reticle 530 not meeting the inspection requirement. In addition, responsive to determining that a storage location 520 is not available, or determining that reticle inspection system 506 is in use, reticle 530 is not moved from single reticle pod 540 for inspection at all.

[0099] Load port 518 is a mechatronic device where a reticle 530 pod 540 can be loaded into and unloaded from reticle handler 502. A user can place a pod 540 with a reticle 540 on load port 518. Load port 518 locks pod 540 to load port 518 and opens its cover to allow movement arm 512 to pick up reticle 530. When a reticle 530 needs to be unloaded from system 500, an empty pod 540 is placed on load port 518, load port 518 unlocks and opens it, then movement arm 512 places a reticle 530 into pod 540, and the load port 518 closes and locks pod 540. The user can then take pod 540 away together with reticle 530 inside.

[0100] Fig. 6 illustrates a flow diagram for a flow 600 for inspecting and storing reticles within a reticle handler. Flow 600 begins with reticle identification 602 (e.g., with a reticle in a single reticle pod). Identification 602 may be based on one or more identifiers such as a bar code, a serial number, an RFID tag, etc., associated with the reticle. A determination 604 is made as to whether a storagelocation in reticle storage (e.g., a reticle library, see Fig. 5) is available. If not (“no” at 604), no further action is taken and flow 600 stops 606. If a storage location in the reticle storage is available (“yes” at 604), a determination 608 is made as to whether a reticle inspection system (e.g., see Fig. 5) is in use. Note that, some embodiments, determinations 604 and 608 may be executed in reverse order, or substantially concurrently. Returning to flow 600, if the reticle inspection system is in use, (“yes” at 608), no further action is taken and flow 600 stops 606. However, responsive to determining that the storage location is available (“yes” at 604) and determining that the reticle inspection system is not in use (“no” at 608), the reticle identified at 602 is moved 610 (e.g., by a reticle handler comprising a movement arm with a gripper - see Fig. 5) for inspection 612 by the reticle inspection system. Responsive to the reticle meeting an inspection requirement (“yes” at 612), the reticle is moved 614 to the storage location to store the reticle. If the reticle does not meet the inspection requirement (“no” at 612), the reticle is placed back into the pod, or otherwise not placed into reticle storage.

[0101] Fig. 7 is a block diagram that illustrates a computer system 700 that is part of and / or can assist in implementing the methods, flows, and / or the system(s) described herein. Computer system 700 may be included in and / or be electronically coupled to lithography apparatuses LA (Fig. 1), lithography apparatus 300 (Fig. 3A, 3B, 3C), and / or lithography apparatus 510 (Fig. 5) described above; reticle handlers 306 (Fig. 3A, 3B, 3C) and / or reticle handler 502 (Fig. 5); and / or other components. Computer system 700 includes a bus 702 or other communication mechanism for communicating information, and a processor 704 (or multiple processors 704, 705, etc., any or all of which may be the same as or similar to processor 504 shown in Fig. 5) coupled with bus 702 for processing information. Computer system 700 also includes a main memory 706, such as a random access memory (RAM) or other dynamic storage device, coupled to bus 702 for storing information and instructions to be executed by processor 704. Main memory 706 also may be used for storing temporary variables or other intermediate information during execution of instructions to be executed by processor 704. Computer system 700 further includes a read only memory (ROM) 708 or other static storage device coupled to bus 702 for storing static information and instructions for processor 704. A storage device 710, such as a magnetic disk or optical disk, is provided and coupled to bus 702 for storing information and instructions.

[0102] Computer system 700 may be coupled via bus 702 to a display 712, such as a flat panel or touch panel display for displaying information to a computer user (which may be similar to and / or the same as user interface 516 described in Fig. 5). An input device 714 (which could be the touch panel), including alphanumeric and other keys, is coupled to bus 702 for communicating information and command selections (e.g., user entries and / or selections) to processor 704. Another type of user input device is cursor control 716, such as a mouse, a trackball, or cursor direction keys for communicating direction information and command selections to processor 704 and for controlling cursor movement on display 712. 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.

[0103] In some embodiments, portions of one or more flows and / or methods described herein may be performed by computer system 700 in response to processor 704 executing one or more sequences of one or more instructions contained in main memory 706. Such instructions may be read into main memory 706 from another computer-readable medium, such as storage device 710. Execution of the sequences of instructions contained in main memory 706 causes processor 704 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 706. In some embodiments, hard-wired circuitry may be used in place of or in combination with software instructions. Thus, the present systems and methods are not limited to any specific combination of hardware circuitry and software.

[0104] The term “computer-readable medium” or “machine readable medium” refers to any medium that participates in providing instructions to processor 704 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 710. Volatile media include dynamic memory, such as main memory 706. Transmission media include coaxial cables, copper wire and fiber optics, including the wires that comprise bus 702. 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.

[0105] Various forms of computer readable media may be involved in carrying one or more sequences of one or more instructions to processor 704 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 702 carries the data to main memory 706, from which processor 704 retrieves and executes the instructions. The instructions received by main memory 706 may optionally be stored on storage device 710 either before or after execution by processor 704.

[0106] Computer system 700 may also include a communication interface 718 coupled to bus 702. Communication interface 718 provides a two-way data communication coupling to a network link 720 that is connected to a local network 722. For example, communication interface 718 may be a local area network (LAN) card to provide a data communication connection to a compatible LAN. Wireless links may also be implemented. In any such implementation, communication interface 718 sends andreceives electrical, electromagnetic, or optical signals that carry digital data streams representing various types of information.

[0107] Network link 720 typically provides data communication through one or more networks to other data devices. For example, network link 720 may provide a connection through local network 722 to a host computer 724 or to data equipment operated by an Internet Service Provider (ISP) 726. ISP 726 in turn provides data communication services through internet 728. Local network 722 and internet 728 both use electrical, electromagnetic, or optical signals that carry digital data streams. The signals through the various networks and the signals on network link 720 and through communication interface 718, which carry the digital data to and from computer system 700, are exemplary forms of carrier waves transporting the information.

[0108] Computer system 700 can send messages and receive data, including program code, through the network(s), network link 720, and communication interface 718. In the Internet example, a server 730 might transmit a requested code for an application program through Internet 728, ISP 726, local network 722 and communication interface 718. One such downloaded application may provide all or part of a method described herein, for example. The received code may be executed by processor 704 as it is received, and / or stored in storage device 710, or other non-volatile storage for later execution. In this manner, computer system 700 may obtain application code in the form of a carrier wave.

[0109] Various embodiments of the present systems and methods are disclosed in the subsequent list of numbered clauses:1. A method for inspecting and storing reticles within a reticle handler, the reticle handler comprising a reticle inspection system and reticle storage, the method comprising: determining whether a storage location in the reticle storage is available; determining whether the reticle inspection system is in use; responsive to determining that the storage location is available and determining that the reticle inspection system is not in use, moving a reticle for inspection by the reticle inspection system; and responsive to the reticle meeting an inspection requirement, moving the reticle to the storage location to store the reticle.2. The method of clause 1 , wherein the reticle is identified and moved from a single reticle pod for inspection.3. The method of any of the previous clauses, wherein the single reticle pod is separate from the reticle handler.4. The method of any of the previous clauses, wherein the reticle handler further comprises a movement arm with a gripper, the movement arm with the gripper configured to grip the reticle and: move the reticle from the single reticle pod for inspection, and move the reticle to the available storage location responsive to the reticle meeting the inspection requirement, or move the reticle back to the single reticle pod responsive to the reticle not meeting the inspection requirement.5. The method of any of the previous clauses, wherein responsive to determining that the storage location is not available, or determining that the reticle inspection system is in use, the reticle is notmoved from the single reticle pod for inspection.6. The method of any of the previous clauses, wherein the inspection requirement is associated with contamination of the reticle.7. The method of any of the previous clauses, wherein moving the reticle to the storage location to store the reticle responsive to the reticle meeting the inspection requirement reduces or prevents contamination of the reticle storage.8. The method of any of the previous clauses, wherein the reticle handler is associated with a lithography apparatus used for semiconductor manufacturing.9. The method of any of the previous clauses, wherein the reticle storage comprises a reticle library for the lithography apparatus.10. The method of any of the previous clauses, wherein the lithography apparatus is a deep ultraviolet (DUV) lithography apparatus.11. The method of any of the previous clauses, wherein the lithography apparatus is an extreme ultraviolet (EUV) lithography apparatus.12. The method of any of the previous clauses, wherein initiating reticle inspection and storage responsive to determining that the storage location is available and determining that the reticle inspection system is not in use enhances reticle throughput by reducing necessary movements performed by the reticle handler.13. The method of any of the previous clauses, further comprising identifying the reticle based on one or more identifiers coupled to the reticle prior to moving the reticle for inspection.14. The method of any of the previous clauses, wherein the one or more identifiers comprise a bar code, a serial number, and / or a radio frequency identification (RFID) tag.15. The method of any of the previous clauses, wherein the reticle handler further comprises one or more processors, and the method further comprises facilitating, with the one or more processors, user enabling or disabling of the available storage location and reticle inspection system use determinations prior to inspection and / or storage of the reticle.16. The method of any of the previous clauses, wherein the one or more processors facilitate the enabling or disabling by causing display of one or more user instruction entry and / or selection fields via a user interface associated with the reticle handler, the enabling or disabling causing configuration changes in the reticle handler depending on whether a user desires the reticle handler to determine whether the storage location in the reticle storage is available, and determine whether the reticle inspection system is in use, prior to moving the reticle for inspection.17. The method of any of the previous clauses, wherein the storage location comprises a slot for the reticle in the reticle storage.18. The method of any of the previous clauses, wherein reticle storage comprises up to five, ten, fifteen, or twenty slots, each of which potentially comprises an available storage location.19. The method of any of the previous clauses, further comprising performing the inspection andgenerating, with the inspection system, image data comprising one or more images of a surface of the reticle from a microscope inspection.20. The method of any of the previous clauses, further comprising analyzing the image data for presence of contamination, and determining that the reticle meets the inspection requirement responsive to an amount of contamination meeting a contamination threshold.21. A non-transitory computer readable medium having instructions thereon, the instructions when executed by a computer causing the computer to: determine whether a storage location in reticle storage associated with a reticle handler is available; determine whether a reticle inspection system of the reticle handler is in use; responsive to determining that the storage location is available and determining that the reticle inspection system is not in use, cause movement of a reticle for inspection by the reticle inspection system; and responsive to the reticle meeting an inspection requirement, cause movement of the reticle to the storage location to store the reticle.22. The medium of clause 21, wherein the reticle is identified and moved from a single reticle pod for inspection.23. The medium of any of the previous clauses, wherein the single reticle pod is separate from the reticle handler.24. The medium of any of the previous clauses, wherein the reticle handler further comprises a movement arm with a gripper, the movement arm with the gripper configured to grip the reticle, and the instructions further cause the computer to: cause the movement arm to and the gripper to move the reticle from the single reticle pod for inspection, and cause the movement arm and the gripper to move the reticle to the available storage location responsive to the reticle meeting the inspection requirement, or move the reticle back to the single reticle pod responsive to the reticle not meeting the inspection requirement.25. The medium of any of the previous clauses, wherein responsive to determining that the storage location is not available, or determining that the reticle inspection system is in use, the reticle is not moved from the single reticle pod for inspection.26. The medium of any of the previous clauses, wherein the inspection requirement is associated with contamination of the reticle.27. The medium of any of the previous clauses, wherein moving the reticle to the storage location to store the reticle responsive to the reticle meeting the inspection requirement reduces or prevents contamination of the reticle storage.28. The medium of any of the previous clauses, wherein the reticle handler is associated with a lithography apparatus used for semiconductor manufacturing.29. The medium of any of the previous clauses, wherein the reticle storage comprises a reticle library for the lithography apparatus.30. The medium of any of the previous clauses, wherein the lithography apparatus is a deep ultraviolet (DUV) lithography apparatus.31. The medium of any of the previous clauses, wherein the lithography apparatus is an extreme ultraviolet (EUV) lithography apparatus.32. The medium of any of the previous clauses, wherein initiating reticle inspection and storage responsive to determining that the storage location is available and determining that the reticle inspection system is not in use enhances reticle throughput by reducing necessary movements performed by the reticle handler.33. The medium of any of the previous clauses, wherein the instructions further cause the computer to identify the reticle based on one or more identifiers coupled to the reticle prior to causing movement of the reticle for inspection.34. The medium of any of the previous clauses, wherein the one or more identifiers comprise a bar code, a serial number, and / or a radio frequency identification (RFID) tag.35. The medium of any of the previous clauses, wherein the reticle handler further comprises one or more processors, and the instructions further cause the computer to facilitate, with the one or more processors, user enabling or disabling of the available storage location and reticle inspection system use determinations prior to inspection and / or storage of the reticle.36. The medium of any of the previous clauses, wherein the one or more processors facilitate the enabling or disabling by causing display of one or more user instruction entry and / or selection fields via a user interface associated with the reticle handler, the enabling or disabling causing configuration changes in the reticle handler depending on whether a user desires the reticle handler to determine whether the storage location in the reticle storage is available, and determine whether the reticle inspection system is in use, prior to moving the reticle for inspection.37. The medium of any of the previous clauses, wherein the storage location comprises a slot for the reticle in the reticle storage.38. The medium of any of the previous clauses, wherein reticle storage comprises up to five, ten, fifteen, or twenty slots, each of which potentially comprises an available storage location.39. The medium of any of the previous clauses, wherein the instructions further cause the computer to control the inspection system to perform the inspection and generate image data comprising one or more images of a surface of the reticle from a microscope inspection.40. The medium of any of the previous clauses, wherein the instructions further cause the computer to control the inspection system to analyze the image data for presence of contamination, and determine that the reticle meets the inspection requirement responsive to an amount of contamination meeting a contamination threshold.41. A system for inspecting and storing reticles, the system comprising: a reticle handler, the reticle handler comprising a reticle inspection system and reticle storage; and one or more processors configured to: determine whether a storage location in the reticle storage is available; determine whether the reticle inspection system is in use; responsive to determining that the storage location is available and determining that the reticle inspection system is not in use, causing movement of areticle for inspection by the reticle inspection system; and responsive to the reticle meeting an inspection requirement, causing movement of the reticle to the storage location to store the reticle.42. The system of clause 41, wherein the reticle is identified and moved from a single reticle pod for inspection.43. The system of any of the previous clauses, wherein the single reticle pod is separate from the reticle handler.44. The system of any of the previous clauses, wherein the reticle handler further comprises a movement arm with a gripper, the movement arm with the gripper configured to grip the reticle, and wherein the one or more processors are further configured to: cause the movement arm with the gripper to move the reticle from the single reticle pod for inspection, and cause the movement arm with the gripper to move the reticle to the available storage location responsive to the reticle meeting the inspection requirement, or move the reticle back to the single reticle pod responsive to the reticle not meeting the inspection requirement.45. The system of any of the previous clauses, wherein responsive to determining that the storage location is not available, or determining that the reticle inspection system is in use, the reticle is not moved from the single reticle pod for inspection.46. The system of any of the previous clauses, wherein the inspection requirement is associated with contamination of the reticle.47. The system of any of the previous clauses, wherein moving the reticle to the storage location to store the reticle responsive to the reticle meeting the inspection requirement reduces or prevents contamination of the reticle storage.48. The system of any of the previous clauses, wherein the reticle handler is associated with a lithography apparatus used for semiconductor manufacturing.49. The system of any of the previous clauses, wherein the reticle storage comprises a reticle library for the lithography apparatus.50. The system of any of the previous clauses, wherein the lithography apparatus is a deep ultraviolet (DUV) lithography apparatus.51. The system of any of the previous clauses, wherein the lithography apparatus is an extreme ultraviolet (EUV) lithography apparatus.52. The system of any of the previous clauses, wherein initiating reticle inspection and storage responsive to determining that the storage location is available and determining that the reticle inspection system is not in use enhances reticle throughput by reducing necessary movements performed by the reticle handler.53. The system of any of the previous clauses, wherein the reticle handler is configured to identify the reticle based on one or more identifiers coupled to the reticle prior to moving the reticle for inspection.54. The system of any of the previous clauses, wherein the one or more identifiers comprise a barcode, a serial number, and / or a radio frequency identification (RFID) tag.55. The system of any of the previous clauses, wherein the reticle handler further comprises the one or more processors, and the one or more processors are configured to facilitate user enabling or disabling of the available storage location and reticle inspection system use determinations prior to inspection and / or storage of the reticle.56. The system of any of the previous clauses, wherein the one or more processors facilitate the enabling or disabling by causing display of one or more user instruction entry and / or selection fields via a user interface associated with the reticle handler, the enabling or disabling causing configuration changes in the reticle handler depending on whether a user desires the reticle handler to determine whether the storage location in the reticle storage is available, and determine whether the reticle inspection system is in use, prior to moving the reticle for inspection.57. The system of any of the previous clauses, wherein the storage location comprises a slot for the reticle in the reticle storage.58. The system of any of the previous clauses, wherein reticle storage comprises up to five, ten, fifteen, or twenty slots, each of which potentially comprises an available storage location.59. The system of any of the previous clauses, wherein the reticle inspection system is configured to perform the inspection and generate image data comprising one or more images of a surface of the reticle from a microscope inspection.60. The system of any of the previous clauses, wherein the reticle inspection system is configured to analyze the image data for presence of contamination, and determine that the reticle meets the inspection requirement responsive to an amount of contamination meeting a contamination threshold.61. 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 reticle onto the photoresist layer; and removing a portion of the photoresist layer to form a pattern over the substrate; wherein prior to the receiving, the reticle is inspected and stored with a reticle handler, the reticle handler comprising a reticle inspection system and reticle storage, the inspecting and storing comprising: determining whether a storage location in the reticle storage is available; determining whether the reticle inspection system is in use; responsive to determining that the storage location is available and determining that the reticle inspection system is not in use, moving a reticle for inspection by the reticle inspection system; and responsive to the reticle meeting an inspection requirement, moving the reticle to the storage location to store the reticle.

[0110] 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) lithography and / or DUV lithography that is capable of producing a 193nm wavelength with the use of an ArF laser, and / or 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 asynchrotron or by irradiating a material (either solid or a plasma) with high energy electrons in order to produce photons within this range.

[0111] 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 reticle handler, and the associated lithography apparatus may comprise separate embodiments, and / or these features may be used together in the same embodiment.

[0112] 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 method for inspecting and storing reticles within a reticle handler, the reticle handler comprising a reticle inspection system and reticle storage, the method comprising: determining whether a storage location in the reticle storage is available; determining whether the reticle inspection system is in use; responsive to determining that the storage location is available and determining that the reticle inspection system is not in use, moving a reticle for inspection by the reticle inspection system; and responsive to the reticle meeting an inspection requirement, moving the reticle to the storage location to store the reticle.

2. The method of claim 1, wherein: the reticle is identified and moved from a single reticle pod for inspection; and the single reticle pod is separate from the reticle handler;3. The method of claim 2, wherein the reticle handler further comprises a movement arm with a gripper, the movement arm with the gripper configured to grip the reticle and: move the reticle from the single reticle pod for inspection, and move the reticle to the available storage location responsive to the reticle meeting the inspection requirement, or move the reticle back to the single reticle pod responsive to the reticle not meeting the inspection requirement.

4. The method of claim 2, wherein responsive to determining that the storage location is not available, or determining that the reticle inspection system is in use, the reticle is not moved from the single reticle pod for inspection.

5. The method of claim 1, wherein: the inspection requirement is associated with contamination of the reticle; and moving the reticle to the storage location to store the reticle responsive to the reticle meeting the inspection requirement reduces or prevents contamination of the reticle storage.

6. The method of claim 1, wherein: the reticle handler is associated with a lithography apparatus used for semiconductor manufacturing; the reticle storage comprises a reticle library for the lithography apparatus; and the lithography apparatus is a deep ultraviolet (DUV) lithography apparatus or an extreme ultraviolet (EUV) lithography apparatus.

7. The method of claim 1, wherein initiating reticle inspection and storage responsive to determining that the storage location is available and determining that the reticle inspection system is not in use enhances reticle throughput by reducing necessary movements performed by the reticle handler.

8. The method of claim 1, further comprising identifying the reticle based on one or more identifiers coupled to the reticle prior to moving the reticle for inspection, wherein the one or more identifiers comprise a bar code, a serial number, and / or a radio frequency identification (RFID) tag.

9. The method of any claim 1, wherein: the reticle handler further comprises one or more processors, and the method further comprises facilitating, with the one or more processors, user enabling or disabling of the available storage location and reticle inspection system use determinations prior to inspection and / or storage of the reticle; and the one or more processors facilitate the enabling or disabling by causing display of one or more user instruction entry and / or selection fields via a user interface associated with the reticle handler, the enabling or disabling causing configuration changes in the reticle handler depending on whether a user desires the reticle handler to determine whether the storage location in the reticle storage is available, and determine whether the reticle inspection system is in use, prior to moving the reticle for inspection.

10. The method of claim 1, wherein the storage location comprises a slot for the reticle in the reticle storage.

11. The method of claim 10, wherein reticle storage comprises up to five, ten, fifteen, or twenty slots, each of which potentially comprises an available storage location.

12. The method of claim 1, further comprising performing the inspection and generating, with the inspection system, image data comprising one or more images of a surface of the reticle from a microscope inspection.

13. The method of claim 12, further comprising analyzing the image data for presence of contamination, and determining that the reticle meets the inspection requirement responsive to an amount of contamination meeting a contamination threshold.

14. A non-transitory computer readable medium having instructions thereon, the instructions when executed by a computer causing the computer to: determine whether a storage location in reticle storage associated with a reticle handler is available; determine whether a reticle inspection system of the reticle handler is in use; responsive to determining that the storage location is available and determining that the reticle inspection system is not in use, cause movement of a reticle for inspection by the reticle inspection system; and responsive to the reticle meeting an inspection requirement, cause movement of the reticle to the storage location to store the reticle.

15. A system for inspecting and storing reticles, the system comprising: a reticle handler, the reticle handler comprising a reticle inspection system and reticle storage; and one or more processors configured to: determine whether a storage location in the reticle storage is available; determine whether the reticle inspection system is in use; responsive to determining that the storage location is available and determining that the reticle inspection system is not in use, causing movement of a reticle for inspection by the reticle inspection system; and responsive to the reticle meeting an inspection requirement, causing movement of the reticle to the storage location to store the reticle.

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