KR20230142507A - Augmented Reality (AR) Assisted Particle Contamination Detection - Google Patents

Abstract

An augmented reality (AR) headset includes one or more sensors and a processor coupled to the one or more sensors. One or more sensors may be configured to scan the surface of an object during inspection. The processor may be configured to process information obtained using one or more sensors in real time during the inspection. The processor may be further configured to determine whether contaminants are present on the surface of the object based on the processed information. Additionally, the processor may be further configured to display an image of the contaminant to the user of the AR headset in response to determining that contaminant is present on the surface of the object.

Description

Augmented Reality (AR) Assisted Particle Contamination Detection

This application claims priority from U.S. Provisional Patent Application No. 63/149,783, filed February 16, 2021, which is hereby incorporated by reference in its entirety.

The present invention relates to lithography systems, for example inspection systems for detecting contaminants.

A lithographic apparatus is a machine that applies a desired pattern to a substrate, typically a target portion of the substrate. Lithographic devices may be used, for example, in the manufacture of integrated circuits (ICs). In that case, a patterning device, alternatively called a mask or reticle, may be used to create the circuit pattern to be formed on the individual layers of the IC. This pattern can be transferred onto a target portion (eg, comprising a portion of a die, one or several dies) on a substrate (eg, a silicon wafer). Transfer of the pattern is typically performed through imaging onto a layer of radiation-sensitive material (resist) provided on the substrate. Typically, a single substrate will contain a network of adjacent target portions that are sequentially patterned. Known lithographic devices scan the pattern in a given direction (“scanning”-direction) via a so-called stepper, in which each target portion is irradiated by exposing the entire pattern onto the target portion at once, and a radiation beam, This includes a so-called scanner in which each target portion is illuminated by synchronously scanning the target portions parallel or anti-parallel to the scanning direction. Additionally, the pattern may be transferred from the patterning device to the substrate by imprinting the pattern on the substrate.

Another lithography system is an interferometric lithography system in which there is no patterning device, but rather the light beam is split into two beams and the two beams interfere at the target portion of the substrate through the use of a reflection system. Interference causes lines to be formed in the target portion of the substrate.

During a lithographic operation, different processing steps may require different layers to be formed sequentially on the substrate. Sequencing of layers is typically accomplished by swapping different reticles for each pattern transfer process according to the desired pattern for each layer. A typical lithography system operates within subnanometer tolerances with respect to patterns on the reticle and patterns transferred from the reticle onto the wafer. Contaminant particles on the reticle can introduce errors into the transferred patterns. Therefore, it is desirable to maintain a contaminant-free reticle that can accurately transfer patterns onto a wafer with sub-nanometer accuracy.

Within the environment of a lithographic apparatus, for example, reticle handoff, wafer handoff, controlled gas flow, outgassing of vacuum chamber walls, liquid distribution (e.g. photoresist coating), temperature fluctuations, metal deposition, numerous operations. Highly dynamic processes occur, such as possible rapid movement of components and wear of structures. Over time, dynamic processes introduce and accumulate contaminant particles within the lithographic apparatus.

There is a need to provide improved inspection technologies to detect contaminants.

In some embodiments, an augmented reality (AR) headset includes the following components. One or more sensors, and a processor coupled to the one or more sensors. One or more sensors may be configured to scan the surface of an object during inspection. The processor may be configured to process information obtained using one or more sensors in real time during the inspection. The processor may be further configured to determine whether contaminants are present on the surface of the object based on the processed information. Additionally, the processor may be further configured to display an image of the contaminant to the user of the AR headset in response to determining that contaminant is present on the surface of the object.

In some embodiments, the method includes the following operations. Using one or more sensors in an augmented reality (AR) headset to scan the surface of an object during inspection. Processing information obtained using one or more sensors in real time during an inspection. Based on the processed information, determining whether contaminants are present on the surface of the object. In response to determining that a contaminant is present on the surface of an object, showing an image of the contaminant to the user of the AR headset.

In some embodiments, a non-transitory computer-readable medium stores one or more sequences of one or more instructions that are executed by one or more processors to perform the following tasks: Using one or more sensors in an augmented reality (AR) headset to scan the surface of an object during inspection. Processing information obtained using one or more sensors in real time during an inspection. Based on the processed information, determining whether contaminants are present on the surface of the object. In response to determining that a contaminant is present on the surface of an object, showing an image of the contaminant to the user of the AR headset.

With reference to the accompanying drawings, the structure and operation of various embodiments, as well as further features of the present invention, are described in detail below. Note that the present invention is not limited to the specific embodiments described herein. In this specification, these embodiments are presented for illustrative purposes only. Additional embodiments will be apparent to those skilled in the art based on the teachings contained herein.

The accompanying drawings, which are incorporated in and form a part of this specification, illustrate the invention and, together with the description, serve to explain the principles of the invention and to enable any person skilled in the art to make or use the embodiments described herein. .
1A schematically shows a reflective lithography apparatus according to some embodiments.
1B schematically shows a transmission lithography apparatus according to some embodiments.
Figure 2 schematically shows a more detailed view of a reflective lithography apparatus according to some embodiments.
3 schematically shows a lithographic cell according to some embodiments.
4 schematically shows an augmented reality (AR) device according to some embodiments.
BRIEF DESCRIPTION OF THE DRAWINGS The features of the invention will become more apparent from the detailed description set forth below when taken in conjunction with the drawings in which like reference symbols identify corresponding elements throughout. In the drawings, like reference numbers generally indicate identical, functionally similar, and/or structurally similar elements. Additionally, generally, the first digit(s) of a reference number identifies the drawing in which the reference number first appears. Unless otherwise specified, the drawings provided throughout this specification should not be construed as being to scale.

This specification discloses one or more embodiments incorporating the features of the invention. The disclosed embodiment(s) are provided by way of example. The scope of the invention is not limited to the disclosed embodiment(s). The claimed features are defined by the claims appended hereto.

In this specification, embodiment(s) described as “one embodiment,” “one embodiment,” “exemplary embodiment,” etc., and such references mean that the described embodiment(s) has a specific feature, structure, or It is indicated that although all embodiments may include features, not necessarily all embodiments may include specific features, structures or characteristics. Additionally, these phrases do not necessarily refer to the same embodiment. Additionally, it is understood that when a particular feature, structure or characteristic is described in connection with one embodiment, it is within the knowledge of those skilled in the art to cite such feature, structure or characteristic in connection with other embodiments, whether or not explicitly described. do.

In this specification, spatially relative terms such as “beneath”, “below”, “further below”, “above”, “on”, “above”, etc. are used as shown in the drawings for ease of explanation. It can be used to describe the relationship of one element or feature to another element(s) or feature(s). Spatially relative terms are intended to encompass different orientations of the device in use or operation in addition to the orientation shown in the figures. The device may be otherwise oriented (rotated 90 degrees or other orientations) and spatially relative descriptors used herein may likewise be interpreted accordingly.

As used herein, the term “about” refers to the value of a given quantity that may vary based on specific techniques. Based on the specific description, the term "about" may refer to the value of a given quantity varying, for example, within 10 to 30% of the value (e.g., ±10%, ±20%, or ±30% of the value). You can.

Embodiments of the present invention may be implemented in hardware, firmware, software, or any combination thereof. Additionally, embodiments of the invention may be implemented as instructions stored on a machine-readable medium, which may be read and executed by one or more processors. Machine-readable media may include any mechanism for storing or transmitting information in a form readable by a machine (e.g., a computing device). For example, machine-readable media may include read only memory (ROM); RAM (random access memory); magnetic disk storage media; optical storage media; flash memory device; It may include electrical, optical, acoustic, or other types of propagated signals (e.g., carrier waves, infrared signals, digital signals, etc.), and others. Additionally, firmware, software, routines, and/or instructions may be described herein as performing certain operations. However, it should be understood that these descriptions are for convenience only, and that such operations actually occur from computing devices, processors, controllers, or other devices executing firmware, software, routines, instructions, etc. As used herein, the term “non-transitory” may be used to characterize computer-readable media used to store data, information, instructions, etc., with the only exception being transient radio signals.

However, before describing these embodiments in further detail, it is beneficial to present an example environment in which embodiments of the invention may be implemented.

Exemplary Lithography System

1A and 1B schematically represent a lithographic apparatus 100 and 100', respectively, in which embodiments of the invention may be implemented. Lithographic apparatus 100 and 100' each include: an illumination system (illuminator) IL configured to condition a radiation beam B (e.g., deep ultraviolet or extreme ultraviolet radiation); A support structure configured to support a patterning device (e.g., a mask, reticle, or dynamic patterning device) (MA) and connected to a first positioner (PM) configured to accurately position the patterning device (MA) For example, mask table)(MT); and a substrate table (e.g. a wafer) configured to hold a substrate (e.g. a resist coated wafer) W and connected to a second positioner (PW) configured to accurately position the substrate W. table) (WT). Additionally, the lithographic apparatuses 100 and 100' provide a radiation beam B imparted by the patterning device MA onto the target portion C (e.g., comprising one or more dies) of the substrate W. It has a projection system (PS) configured to project the pattern. In the lithographic apparatus 100, the patterning device (MA) and projection system (PS) are reflective. In the lithographic apparatus 100', the patterning device (MA) and projection system (PS) are transmissive.

The illumination system IL may include refractive, reflective, catadioptric, magnetic, electromagnetic, electrostatic or other types of optical components, or any other type of optical components, to direct, shape or control the radiation beam B. It may include various types of optical components, such as combinations thereof.

The support structure (MT) can be configured to control the orientation of the patterning device (MA) relative to a reference frame, the design of at least one of the lithographic apparatuses 100 and 100', and other conditions such as whether the patterning device (MA) is maintained in a vacuum environment. Maintain the patterning device (MA) in a manner dependent on the The support structure (MT) may utilize mechanical, vacuum, electrostatic, or other clamping techniques to hold the patterning device (MA). The support structure MT can be, for example, a frame or table that can be fixed or movable as required. By using sensors, the support structure MT can ensure that the patterning device MA is in the desired position, for example with respect to the projection system PS.

The term “patterning device” (MA) refers to any device that can be used to impart a pattern to the cross-section of a radiation beam (B) to create a pattern in the target portion (C) of the substrate (W). It should be interpreted broadly. The pattern imparted to the radiation beam B will correspond to a specific functional layer within the device to be created in the target portion C to form an integrated circuit.

The patterning device MA may be transmissive (such as lithographic apparatus 100' in Figure 1B) or reflective (such as lithographic apparatus 100' in Figure 1A). Examples of patterning devices (MAs) include reticles, masks, programmable mirror arrays, and programmable LCD panels. Masks are well known in the field of lithography and include mask types such as binary, alternating phase shift and attenuated phase shift, and various hybrid mask types. One example of a programmable mirror array employs a matrix configuration of small mirrors, each of which can be individually tilted to reflect an incoming radiation beam in different directions. Tilted mirrors impart a pattern to the radiation beam (B), which is reflected by a matrix of small mirrors.

The term "projection system" (PS) refers to the refractive, reflective, catadioptric, catadioptric, or optical beams, as appropriate with respect to the exposure radiation used or with respect to other factors such as the use of an immersion liquid or the use of a vacuum on the substrate W. It can encompass any type of projection system, including magnetic, electromagnetic and electrostatic optical systems, or any combination thereof. A vacuum environment can be used for EUV or electron beam radiation because other gases may absorb too much radiation or electrons. Therefore, with the help of vacuum walls and vacuum pumps, a vacuum environment can be provided over the entire beam path.

Lithographic apparatus 100 and/or lithographic apparatus 100' may be of a type having two (dual stage) or more substrate tables WT (and/or two or more mask tables). In these “multiple stage” machines, additional substrate tables WT may be used in parallel, or preparatory steps may be performed on one or more substrate tables WT while one or more other tables are being used for exposure. In some situations, the additional table may not be a substrate table (WT).

Additionally, the lithographic apparatus may be of a type in which at least a part of the substrate can be covered with a liquid with a relatively high refractive index, such as water, to fill the space between the projection system and the substrate. Additionally, the immersion liquid may be applied to other spaces within the lithographic apparatus, for example between the mask and the projection system. Immersion techniques are well known in the art for increasing the numerical aperture of a projection system. The term “immersion” as used herein does not mean that a structure, such as a substrate, must be submerged in a liquid, but rather simply means that the liquid is placed between the projection system and the substrate during exposure.

1A and 1B, the illuminator IL receives a radiation beam from the radiation source SO. For example, if the source SO is an excimer laser, the source SO and the lithography apparatuses 100 and 100' may be separate physical entities. In this case, the source SO is not considered to form part of the lithographic apparatus 100 or 100', and the radiation beam B is formed, for example, by means of a suitable directing mirror and/or a beam expander. With the help of the beam delivery system BD (see Figure 1b), it passes from the source SO to the illuminator IL. In other cases, the source SO may be an integral part of the lithographic apparatus 100, 100', for example if the source SO is a mercury lamp. The source SO and the illuminator IL may, if necessary together with the beam delivery system BD, be referred to as a radiation system.

The illuminator IL may include an adjuster AD (see FIG. 1B) that adjusts the angular intensity distribution of the radiation beam. In general, at least the outer and/or inner radial dimensions of the intensity distribution within the pupil plane of the illuminator (commonly referred to as “outer-σ” and “inner-σ” respectively) can be adjusted. Additionally, the illuminator IL may include various other components (see FIG. 1B), such as an integrator IN and a condenser CO. The illuminator IL may be used to condition the radiation beam B so as to have a desired uniformity and intensity distribution in the cross section of the radiation beam.

1A, a radiation beam B is incident on a patterning device (e.g., a mask) (MA) held on a support structure (e.g., a mask table) (MT), and the patterning device (MA) ) is patterned by. In lithographic apparatus 100, radiation beam B is reflected from a patterning device (e.g., mask) MA. After reflecting from the patterning device (e.g. mask) MA, the radiation beam B passes through the projection system PS, which directs the radiation beam B onto the target portion C of the substrate W. Focus. With the help of a second positioner (PW) and a position sensor (IF2) (e.g. an interferometric device, linear encoder, or capacitive sensor), the substrate table (WT) is can be accurately moved to position different target portions (C) within the path of. Similarly, the first positioner PM and another position sensor IF1 can be used to accurately position the patterning device (e.g. mask) MA with respect to the path of the radiation beam B. . Patterning device (eg, mask) MA and substrate W may be aligned using mask alignment marks M1, M2 and substrate alignment marks P1, P2.

Referring to FIG. 1B , radiation beam B is incident on a patterning device (e.g., mask) (MA) held on a support structure (e.g., mask table) (MT) and is formed by the patterning device. It is patterned. Having crossed the mask MA, the radiation beam B passes through the projection system PS, which focuses the beam onto the target portion C of the substrate W. The projection system has an illumination system pupil (IPU) and a conjugate pupil (PPU). Portions of the radiation emerge from the intensity distribution in the illumination system pupil (IPU), traverse the mask pattern without being affected by diffraction in the mask pattern, and produce an image of the intensity distribution in the illumination system pupil (IPU).

The projection system PS projects an image MP' of the mask pattern MP onto the photoresist layer coated on the substrate W, where the image MP' is projected onto the mask pattern MP by radiation from the intensity distribution. It is formed by diffracted beams generated from (MP). For example, the mask pattern MP may include an array of lines and spaces. Different from zero-order diffraction, diffraction of radiation in an array produces diffracted beams that deviate from a direction perpendicular to the lines. Non-diffracted beams (i.e. so-called zero-order diffracted beams) traverse the pattern without any change in the direction of propagation. The zeroth order diffracted beams traverse the upper lens or upper lens group of the projection system (PS) upstream of the pupil conjugate (PPU) of the projection system (PS) and reach the pupil conjugate (PPU). The part of the intensity distribution associated with the zero-order diffracted beam in the plane of the conjugate pupil (PPU) is the image of the intensity distribution in the illumination system pupil (IPU) of the illumination system IL. For example, an aperture device (PD) is disposed in or substantially in a plane containing the conjugate pupil (PPU) of the projection system (PS).

The projection system PS is arranged by means of a lens or lens group L to capture not only the zeroth order diffracted beam but also the first or first and higher order diffracted beams (not shown). In some embodiments, dipole illumination for imaging line patterns extending in a direction perpendicular to the line may be used to take advantage of the resolution enhancement effect of dipole illumination. For example, the first-order diffracted beams may interfere with the corresponding zero-order diffracted beam at the level of the wafer W to produce line Create an image of the pattern (MP). In some embodiments, astigmatism can be reduced by providing radiation poles (not shown) in opposite quadrants of the illumination system pupil (IPU). Additionally, in some embodiments, astigmatism can be reduced by blocking zero-order beams at the conjugate pupil (PPU) of the projection system associated with the radiation pole in opposite quadrants. This is explained in more detail in US 7,511,799 B2, issued March 31, 2009, which is hereby incorporated by reference in its entirety.

With the help of a second positioner (PW) and a position sensor (IF) (e.g., an interferometric device, linear encoder, or capacitive sensor), the substrate table (WT) is can be accurately moved to position different target portions (C) within the path of. Similarly, the first positioner (PM) and another position sensor (not shown in FIG. 1B) may detect the radiation beam (e.g., after mechanical retrieval from a mask library, or during a scan). It can be used to accurately position the mask (MA) relative to the path in (B).

In general, the movement of the mask table MT can be realized with the help of a long-stroke module (coarse positioning) and a short-stroke module (fine positioning), which 1 Forms part of the positioner (PM). Similarly, the movement of the substrate table WT can be realized using long-stroke modules and short-stroke modules, which form part of the second positioner PW. In the case of a stepper (in contrast to a scanner) the mask table MT can only be connected to a short-stroke actuator or can be fixed. The mask MA and substrate W may be aligned using mask alignment marks M1 and M2 and substrate alignment marks P1 and P2. Although the substrate alignment marks (as illustrated) occupy dedicated target portions, they may also be located within spaces between target portions (known as scribe-lane alignment marks). ]. Similarly, in situations where more than one die is provided on the mask MA, mask alignment marks may be placed between the dies.

The mask table (MT) and patterning device (MA) may be within a vacuum chamber (V), and an in-vacuum robot (IVR) may be used to move patterning devices, such as masks, into and out of the vacuum chamber. there is. Alternatively, if the mask table (MT) and patterning device (MA) are outside the vacuum chamber, an out-of-vacuum robot, similar to an in-vacuum robot (IVR), can be used for various transport tasks. can be used Both in-vacuum and out-of-vacuum robots need to be calibrated for smooth transfer of any payload (e.g., mask) to the fixed kinematic mount of the transfer station. there is.

Lithographic apparatus 100 and 100' may be used in at least one of the following modes:

1. In step mode, the support structure (e.g., mask table) (MT) and substrate table (WT) are held essentially stationary, while the entire pattern imparted to the radiation beam (B) moves to the target at a time. It is projected onto the negative (C) image (i.e., single static exposure). Afterwards, the substrate table WT is shifted in the X and/or Y directions so that different target portions C can be exposed.

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

3. In another mode, the support structure (e.g., mask table) MT is maintained in an essentially stationary state by holding a programmable patterning device, and the pattern imparted to the radiation beam B is applied to the target portion (B). C) The substrate table WT is moved or scanned while being projected onto the image. A pulsed radiation source (SO) may be employed, with the programmable patterning device updated as needed after each movement of the substrate table WT, or between successive radiation pulses during a scan. This mode of operation can be easily applied to maskless lithography using programmable patterning devices such as programmable mirror arrays.

Additionally, combinations and/or variations of the above-described modes of use, or completely different modes of use, may be employed.

In some embodiments, a lithographic apparatus may generate DUV and/or EUV radiation. For example, lithographic apparatus 100' may be configured to operate using a DUV source. In another example, lithographic apparatus 100 includes an extreme ultraviolet (EUV) source configured to generate an EUV radiation beam for EUV lithography. Typically, an EUV source is configured in a radiation system and a corresponding illumination system is configured to condition the EUV radiation beam of the EUV source.

Figure 2 shows the lithographic apparatus 100 in more detail, including a source collector device (SO), an illumination system (IL), and a projection system (PS). The source collector device (SO) is constructed and arranged so that a vacuum environment can be maintained within the enclosing structure (220) of the source collector device (SO). EUV radiation-emitting plasma 210 may be formed by a discharge-generated plasma source. EUV radiation may be generated by a gas or vapor, such as Xe gas, Li vapor, or Sn vapor, in which a very hot plasma (210) is generated to emit radiation within the EUV range of the electromagnetic spectrum. The ultra-high temperature plasma 210 is generated, for example, by an electrical discharge resulting in an at least partially ionized plasma. For efficient generation of radiation, a partial pressure of Xe, Li, Sn vapor or any other suitable gas or vapor may be required, for example 10 Pa. In some embodiments, a plasma of excited tin (Sn) is provided to generate EUV radiation.

Radiation emitted by the ultra-hot plasma 210 is directed to an optional gas barrier or contaminant trap 230 (in some cases, a contaminant trap) located within or behind the opening of the source chamber 211. It passes from the source chamber 211 through a barrier or foil trap into the collector chamber 212. Contaminant trap 230 may include a channel structure. Additionally, contaminant trap 230 may include a gas barrier or a combination of a gas barrier and a channel structure. The contaminant trap or contaminant barrier 230, as further referred to herein, includes at least a channel structure.

The collector chamber 212 may comprise a radiation collector (CO), which may be a so-called grazing incidence collector. The radiation collector (CO) has an upstream radiation collector side (251) and a downstream radiation collector side (252). Radiation crossing the collector (CO) may be reflected from a grating spectral filter (240) and focused on a virtual source point (IF). The virtual source point (IF) is commonly referred to as the intermediate focus, and the source collector device is arranged such that the intermediate focus (IF) is located at or near the opening 219 in the surrounding structure 220. The virtual source point (IF) is an image of the radiation-emitting plasma 210. Grating spectral filter 240 is used to specifically suppress infrared (IR) radiation.

Subsequently, the radiation traverses the illumination system IL, which provides a desired uniformity of the radiation intensity in the patterning device MA, as well as a desired angular distribution of the radiation beam 221 in the patterning device MA. It may include a disposed faceted field mirror device 222 and a faceted pupil mirror device 224. Upon reflection of the radiation beam 221 at the patterning device MA, which is held by the support structure MT, a patterned beam 226 is formed, which is projected by the projection system PS. It is imaged via reflective elements 228, 229 onto a substrate W held by a wafer stage or substrate table WT.

In general, more elements than shown may be present in the illumination optics unit (IL) and projection system (PS). The grating spectral filter 240 may be optionally present depending on the type of lithographic device. Additionally, there may be more mirrors than shown in FIG. 2 , for example between 1 and 6 additional reflective elements than shown in FIG. 2 may be present in the projection system PS.

The collector optic (CO) as illustrated in Figure 2 is shown as a nested collector with grazing incidence reflectors 253, 254 and 255, which is just one example of a collector (or collector mirror). The grazing incidence reflectors 253, 254 and 255 are arranged axisymmetrically around the optical axis O and this type of collector optics (CO) is preferably used in combination with a discharge generating plasma source, commonly referred to as a DPP source. do.

Exemplary Lithography Cell

3 shows a lithography cell 300, sometimes referred to as a lithocell or cluster, according to some embodiments. Lithographic apparatus 100 or 100' may form part of lithography cell 300. Additionally, lithography cell 300 may include one or more devices that perform pre-exposure and post-exposure processes on the substrate. Typically, these include a spin coater (SC) to deposit the resist layers, a developer (DE) to develop the exposed resist, a chill plate (CH) and a bake plate (BK). do. A substrate handler or robot (RO) picks up the substrates from the input/output ports (I/O1, I/O2), moves them between different process equipment, and loads the substrates of the lithographic apparatus 100 or 100'. It is delivered to loading bay: LB). These devices, often collectively referred to as tracks, are under the control of a track control unit (TCU), which is itself controlled by a supervisory control system (SCS), which controls the lithography apparatus through a lithography control unit (LACU). Accordingly, different devices can be operated to maximize throughput and processing efficiency.

Exemplary Contaminant Testing Apparatus

In some embodiments, the lithographic apparatus 100 of FIG. 1A and/or the lithographic apparatus 100' of FIG. 1B and the tools associated with servicing such apparatus(s) are capable of producing any imperfections, defects, defects, defects, defects, defects, defects, defects, or other defects of any kind during the manufacturing processes. It requires inspection to determine its cleanliness to avoid defects, etc. Inspection techniques can be performed to prevent undesirable defects on a surface (e.g., the surface of a reticle or substrate). Inspection techniques may include visual inspection of an object with the naked eye. The quality of these tests can depend on the sharpness of vision of the individual examining the object and how attentive the individual is during the test. Additionally, some contaminants may be too small to be detected with the naked eye.

In this specification, terms such as “imperfections,” “defects,” “defects,” and the like may be used to refer to deviations or non-uniformities of structures from specified tolerances. For example, a flat surface may have defects such as scratches, holes, or recesses, foreign particles, stains, etc.

In the context of imperfections, the terms "foreign particles", "contaminant particles", "contaminants", etc. are used herein to refer to particulate matter present on a surface or area not designed to tolerate the presence of undesirable particulate matter, or otherwise present on a surface or area that is not designed to tolerate the presence of particulate matter. may be used to refer to unexpected, unusual, undesirable, or otherwise (herein undesirable) particulate matter that adversely affects the operation of a device present therein. These “foreign particles” and “contaminants” may include, but are not limited to, organic materials such as human tissue/cells, and inorganic contaminants such as metal/alloy debris. Organic contaminants can be a result of the way parts/modules are handled during production, transportation and assembly. Inorganic contaminants may be a result of the technological processes used to manufacture the components/modules. For example, parts/modules may be processed on a lathe or milling machine, generating many small particles in the parts/modules that are still found on the tested surfaces even with multiple subsequent cleaning steps. It can be. Some examples of inorganic contaminants may include dust, stray photoresist, or other dislodged materials within the lithography apparatus. Examples of materials removed may include steel, Au, Ag, Al, Cu, Pd, Pt, Ti, etc. Material removal may occur, for example, due to friction and impact of the structures being actuated and processes fabricating metal interconnects on substrates. Contaminants can enter sensitive parts (eg, reticle or substrate) within the lithography apparatus and increase the potential for errors in lithography processes. Embodiments of the present invention provide structures and functions for detecting defects on sensitive parts of a lithographic process or device.

4 schematically shows an augmented reality (AR) headset 400 according to some embodiments. In some embodiments, AR headset 400 may include one or more sensors 402, a processor 404, and a display 406, such as one or more lenses for showing images to a user. Additionally, those skilled in the art should understand that AR headset 400 may include a frame with arm portions connected to lens retainers. Images may be projected onto at least one lens of display 406 disposed in an opening of the frame. In some embodiments, AR headset 400 may be used to inspect object 410, such as in lithographic apparatus 100 of FIG. 1A or lithographic apparatus 100' of FIG. 1B. As another example, object 410 may be a tool used to service lithographic apparatus 100 of FIG. 1A or lithographic apparatus 100' of FIG. 1B.

In some embodiments, one or more sensors 402 may be one or more image capture devices, such as a camera, configured to capture one or more images of objects 410 . For example, one or more images may be a video feed. In some embodiments, the one or more sensors 402 may be one or more ultrasonic sensors configured to emit ultrasonic waves and receive reflected waves reflected from the object 410 . In some embodiments, the one or more sensors 402 include one or more hyperspectral imaging sensors configured to collect and process information from across the electromagnetic spectrum to obtain a spectrum for each pixel in the image of the object 410; For example, it could be a spatial scanner, a spectral scanner, a snapshot hyperspectral imaging scanner, etc. In some embodiments, the one or more sensors may be any combination of an image capture device, an ultrasonic sensor, and a hyperspectral imaging sensor. Those skilled in the art should understand that these are merely examples of sensors that may be used and that other sensors are further contemplated in accordance with embodiments of the present invention.

In some embodiments, processor 404 may process information from one or more sensors 402 in real time during inspection of object 410 to detect the presence of contaminants on the surface of object 410. For example, one or more image capture devices can capture a video feed during an examination. In this example, processor 404 may analyze the video feed to detect changes in reflected luminosity between two or more spots on the surface of object 410. In some embodiments, a change in reflected brightness between two or more spots may indicate the presence of contaminants.

As another example, for one or more ultrasonic sensors, the processor 404 can measure the time between emission and reception of ultrasonic waves at two or more spots on the surface of the object 410 to measure the time between the AR headset 400 and the object 410. The distance between them can be measured. For example, one or more ultrasonic sensors direct ultrasonic waves to be reflected from the object 410 at a first time t1 and send reflected waves to two or more spots on the surface of the object 410 at a second time t2. You can receive it. The processor 404 may measure the distance to the object by measuring the time between t1 and t2 in each of two or more spots. In some embodiments, processor 404 may be further configured to compare the current distance to a previous distance. In this example, processor 404 may determine that contaminants are present in response to determining a change in distance between the surface of the object and the AR headset by comparing the distances in two or more spots.

In another example, for one or more hyperspectral imaging sensors, processor 404 may analyze the electromagnetic spectrum for each pixel within the image of object 410. In this example, processor 404 may determine that contaminants are present on object 410 based on changes in the electromagnetic spectrum from one pixel to another in two or more spots on the surface of object 410. .

In some embodiments, in response to detecting the presence of contaminants, AR headset 400 may use display 406 to show the user the detected contaminants. In some embodiments, detected contaminants may be enlarged or augmented for display. For example, using one or more sensors, AR headset 400 can capture and magnify an image of contaminants on the surface of object 410 for illustration in display 406.

In some embodiments, AR headset 400 may generate a three-dimensional (3D) map of object 410 . The AR headset 400 can identify the location of contaminants on the object 410 by combining information from one or more sensors and a 3D map. Accordingly, in some embodiments, AR headset 400 may provide location information of contaminants to the user. In some embodiments, the AR headset 400 may log location information of contaminants in storage, for example, storing location information in memory or a database.

The present embodiments can be further explained using the following items:

1. As an augmented reality (AR) headset,

One or more sensors configured to scan the surface of the object during inspection; and

A processor coupled to one or more sensors, comprising:

Processing information obtained using one or more sensors in real time during the inspection;

Based on the processed information, determine whether contaminants are present on the surface of the object; and

An AR headset configured to display an image of the contaminant to a user of the AR headset in response to determining that the contaminant is present on the surface of the object.

2. In clause 1,

The one or more sensors include one or more image capture devices configured to capture video feeds during the inspection,

The AR headset wherein the processor is further configured to analyze the video feed to determine whether a change in reflected brightness has occurred from two or more spots on the surface of the object.

3. The AR headset of clause 2, wherein the processor is further configured to determine the presence of contaminants on the object in response to determining that a change in reflected brightness has occurred.

4. In clause 1,

the at least one sensor comprising at least one ultrasonic sensor configured to direct ultrasonic waves to be reflected from the object at time t1 and to receive the reflected waves for two or more spots on the surface of the object at time t2;

The AR headset wherein the processor is further configured to measure the distance to the object by measuring the time between t1 and t2 in each of the two or more spots.

5. The method of clause 4, wherein to determine whether a contaminant is present on the surface of the object, the processor responds to the determination of the change in distance between the surface of the object and the AR headset by comparing the distances in two or more spots to determine whether the contaminant is present on the surface of the object. An AR headset further configured to determine presence.

6. The AR headset of clause 1, wherein the processor is further configured to generate a three-dimensional (3D) map of the object.

7. The AR headset of clause 6, wherein the processor is further configured to combine information from one or more sensors with the 3D map to identify the location of contaminants on the object.

8. The AR headset of clause 7, wherein the processor is further configured to provide location information of contaminants to the user.

9. Using one or more sensors of an augmented reality (AR) headset, scanning the surface of the object during inspection;

Processing information obtained using one or more sensors in real time during the inspection;

Based on the processed information, determining whether a contaminant is present on the surface of the object; and

In response to determining that a contaminant is present on the surface of the object, a method comprising showing an image of the contaminant to a user of the AR headset.

10. In clause 9,

further comprising using one or more image capture devices as one or more sensors, wherein the one or more image capture devices are configured to capture a video feed during the inspection,

A method wherein the processing step includes analyzing the video feed to determine whether a change in reflected brightness has occurred from two or more spots on the surface of the object.

11. The method of clause 10, wherein determining whether contaminant is present on the surface of the object comprises determining that contaminant is present in response to determining that a change in reflected brightness has occurred.

12. In clause 9,

It further includes using at least one ultrasonic sensor as the at least one sensor, wherein the at least one ultrasonic sensor directs ultrasonic waves to be reflected from the object at time t1 and receives the reflected wave for two or more spots on the surface of the object at time t2. It is composed,

A method wherein the processing step includes measuring the distance to the object by measuring the time between t1 and t2 in each of the two or more spots.

13. The method of clause 12, wherein the step of determining whether contaminants are present on the surface of the object is in response to determining a change in distance between the surface of the object and the AR headset by comparing the distances in two or more spots. A method comprising the steps of determining .

14. The method of clause 9 further comprising generating a three-dimensional (3D) map of the object.

15. The method of clause 14, further comprising combining information from one or more sensors with the 3D map to identify the location of contaminants on the object.

16. The method of clause 15, further comprising providing location information of contaminants to the user.

17. A non-transitory computer-readable medium, comprising:

using one or more sensors of the augmented reality headset to scan the surface of the object during inspection;

Processing information obtained using one or more sensors in real time during the inspection;

Based on the processed information, determining whether contaminants are present on the surface of the object; and

In response to determining that a contaminant is present on the surface of an object, a non-transitory device storing one or more sequences of one or more instructions to be executed by one or more processors to perform tasks including showing an image of the contaminant to a user of the AR headset. Computer-readable media.

18. The non-transitory computer-readable medium of clause 17, wherein the operations further include generating a three-dimensional (3D) map of the object.

19. The non-transitory computer-readable medium of clause 18, wherein the tasks further include combining information from one or more sensors with a 3D map to identify the location of contaminants on the object.

20. The non-transitory computer-readable medium of clause 18, wherein the operations further comprise logging the location of the contaminant in a database.

Although reference is made herein to specific uses of lithographic apparatuses in IC fabrication, lithographic apparatuses described herein may include integrated optical systems, guidance and detection patterns for magnetic domain memories, flat-panel displays, LCDs, etc. , it should be understood that it may have other applications, such as manufacturing thin film magnetic heads, etc. Those skilled in the art will appreciate that, with respect to these alternative applications, any use of the terms "wafer" or "die" herein may be considered synonymous with the more general terms "substrate" or "target section", respectively. You will understand. The substrates referred to herein may be processed before or after exposure, for example in a track unit (typically a tool that applies a layer of resist to the substrate and develops the exposed resist), a metrology unit and/or an inspection unit. . Where applicable, the teachings herein may be applied to these and other substrate processing tools. Additionally, since a substrate may be processed more than once, for example to create a multilayer IC, the term substrate as used herein may also refer to a substrate containing layers that have already been processed multiple times.

Although specific uses of embodiments of the present invention have been mentioned above in relation to optical lithography, it is understood that the present invention can be used in other applications, such as imprint lithography, and is not limited to optical lithography if permitted by the present disclosure. You will understand. In imprint lithography, the topography in the patterning device defines the pattern created on the substrate. The topography of the patterning device can be pressed into a layer of resist supplied to a substrate, and the resist is cured by applying electromagnetic radiation, heat, pressure, or a combination thereof. The patterning device is moved away from the resist after it has cured, leaving a pattern therein.

It is to be understood that any phrase or terminology used herein is for the purpose of description and not limitation, and that any phrase or terminology herein should be construed by those skilled in the art in light of the teachings herein.

As used herein, the term “substrate” describes the material to which layers of material are added. In some embodiments, the substrate itself may be patterned, and materials added thereon may also be patterned, or may be left without patterning.

Although reference is made herein to specific examples of use of devices and/or systems according to the invention in IC manufacturing, it should be clearly understood that such devices and/or systems have numerous other possible applications. For example, this can be employed in the manufacture of integrated optical systems, guidance and detection patterns for magnetic domain memories, LCD panels, thin film magnetic heads, etc. Those skilled in the art will understand that, with respect to these alternative applications, any use of the terms “reticle,” “wafer,” or “die” herein will be replaced by the more general terms “mask,” “substrate,” and “target portion,” respectively. It will be understood that it should be considered to be replaced by .

Although specific embodiments of the invention have been described above, it will be understood that the invention may be practiced otherwise than as described. The above description is not intended to limit the invention.

It should be understood that the Detailed Description section, not the Abstract and Summary sections, is intended to be used in interpreting the claims. The Summary and Abstract sections may describe one or more, but not all exemplary embodiments of the invention as contemplated by the inventor(s), and are therefore not intended to limit the invention and the appended claims in any way. No.

Above, the invention has been described with the help of functional building blocks that illustrate the implementation of specific functions and their relationships. The boundaries of these functional building blocks are arbitrarily defined herein for convenience of description. Alternative boundaries may be defined as long as certain functions and their relationships are performed appropriately.

The foregoing description of specific embodiments is intended to enable, by applying knowledge in the art, these specific embodiments to be easily modified and/or adapted without undue experimentation without departing from the general concept of the invention for various applications. It will reveal all its general properties. Therefore, these applications and variations are intended to be within the meaning and scope of equivalents of the disclosed embodiments, based on the teachings and guidance presented herein.

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

Claims (15)

As an augmented reality (AR) headset,
One or more sensors configured to scan the surface of the object during inspection; and
A processor coupled to the one or more sensors
, wherein the processor:
Process information obtained using the one or more sensors in real time during the inspection;
Based on the processed information, determine whether contaminants are present on the surface of the object; and
in response to determining that the contaminant is present on the surface of the object, configured to show an image of the contaminant to a user of the AR headset,
AR headset. According to claim 1,
the one or more sensors comprise one or more image capture devices configured to capture a video feed during the inspection,
the processor is further configured to analyze the video feed to determine whether a change in reflected luminosity has occurred from two or more spots on the surface of the object,
wherein the processor is further configured to determine the presence of the contaminant on the object in response to determining that a change in reflected brightness has occurred,
AR headset. According to claim 1,
the at least one sensor comprising at least one ultrasonic sensor configured to direct ultrasonic waves to be reflected from the object at time t1 and to receive reflected waves for two or more spots on the surface of the object at time t2;
the processor is further configured to measure the distance to the object by measuring the time between t1 and t2 at each of the two or more spots,
To determine whether the contaminant is present on the surface of the object, the processor is responsive to a determination of a change in distance between the surface of the object and the AR headset by comparing the distances in the two or more spots to determine whether the contaminant is present on the surface of the object. further configured to determine existence,
AR headset. According to claim 1,
the processor is further configured to generate a three-dimensional (3D) map of the object,
the processor is further configured to combine information from the one or more sensors and the 3D map to identify the location of contaminants on the object,
wherein the processor is further configured to provide location information of the contaminant to a user,
AR headset. Using one or more sensors of an augmented reality (AR) headset, scanning the surface of the object during inspection;
processing information obtained using the one or more sensors in real time during the inspection;
Based on the processed information, determining whether contaminants are present on the surface of the object; and
In response to determining that the contaminant is present on the surface of the object, showing an image of the contaminant to a user of the AR headset.
Method, including. According to claim 5,
further comprising using one or more image capture devices as the one or more sensors, wherein the one or more image capture devices are configured to capture a video feed during the inspection,
The method of claim 1, wherein the processing step includes analyzing the video feed to determine whether a change in reflected brightness has occurred from two or more spots on the surface of the object. According to claim 6,
Wherein determining whether the contaminant is present on the surface of the object comprises determining that the contaminant is present in response to determining that a change in reflected brightness has occurred. According to claim 5,
It further includes using at least one ultrasonic sensor as the at least one sensor, wherein the at least one ultrasonic sensor directs ultrasonic waves to be reflected from the object at time t1 and to two or more spots on the surface of the object at time t2. Configured to receive reflected waves,
The method of claim 1, wherein the processing step includes measuring the distance to the object by measuring the time between t1 and t2 at each of the two or more spots. According to claim 8,
Determining whether the contaminant is present on the surface of the object may include determining that the contaminant is present in response to a determination of a change in distance between the surface of the object and the AR headset by comparing distances in the two or more spots. A method comprising the step of determining. According to claim 5,
generating a three-dimensional (3D) map of the object; and
The method further comprising combining information from the one or more sensors with the 3D map to identify the location of contaminants on the object. According to claim 10,
The method further comprising providing location information of the contaminant to a user. A non-transitory computer-readable medium, comprising:
using one or more sensors of the augmented reality headset to scan the surface of the object during inspection;
processing information obtained using the one or more sensors in real time during the inspection;
Based on the processed information, determining whether contaminants are present on the surface of the object; and
In response to determining that the contaminant is present on the surface of the object, showing the user of the AR headset an image of the contaminant.
storing one or more sequences of one or more instructions to be executed by one or more processors to perform tasks including,
Non-transitory computer-readable media. According to claim 12,
The tasks further include generating a three-dimensional (3D) map of the object,
Non-transitory computer-readable media. According to claim 13,
The tasks further include combining information from the one or more sensors and the 3D map to identify the location of contaminants on the object.
Non-transitory computer-readable media. According to claim 13,
The operations further include logging the location of the contaminant in a database,
Non-transitory computer-readable media.

Images