System and method for non-linear optical metrology for advanced sub-diffraction imaging

Abstract

A sensor device may include an instantaneous optical pattern, a probe beam, and a detector. The instantaneous optical pattern may be configured to induce a material change of the alignment mark, thereby forming an effective alignment mark. The probe beam may be configured to interact with the active alignment mark. The detector may be configured to measure diffracted light generated by the probe beam from the effective alignment mark. Advantageously, the sensor device may utilize visible light to initiate an instantaneous change in the refractive index of the alignment mark, detect the sub-wavelength characteristics of the alignment mark, measure the asymmetry of the alignment mark, and increase the resolution of the sensor device to at least four times.

Description

[0001] Cross-reference to related applications

[0002] This application claims priority to U.S. Application No. 63 / 515,749, filed July 26, 2023, the entire contents of which are incorporated herein by reference. Technical Field

[0003] This disclosure relates to optical measurement systems and methods, such as optical measurement systems and methods for lithography equipment and systems. Background Technology

[0004] A lithography apparatus is a machine configured to apply a desired pattern onto a substrate. Lithography apparatus can be used, for example, in the manufacture of integrated circuits (ICs). A lithography apparatus can project a pattern from a patterning apparatus (e.g., a mask, a photomask) onto a radiation-sensitive material (resist) layer disposed on a substrate.

[0005] To project a pattern onto a substrate, a photolithography apparatus can use electromagnetic radiation. The wavelength of this radiation determines the minimum size of the feature that can be formed on the substrate. Compared to photolithography apparatuses using deep ultraviolet (DUV) radiation with wavelengths of, for example, 157 nm, 193 nm, or 248 nm, photolithography apparatuses using extreme ultraviolet (EUV) radiation with wavelengths in the range of 4 nm to 20 nm (e.g., 6.7 nm or 13.5 nm) can be used to form smaller features on the substrate.

[0006] To control the photolithography process for accurately forming device features on a substrate, one or more targets can be formed on the substrate and used for alignment and positioning. The photolithography apparatus can use one or more sensors to accurately measure the characteristics of a target by illuminating light at the target (e.g., alignment marks) and collecting the light diffracted from the target. Current alignment systems and techniques are subject to certain drawbacks and limitations. For example, previous systems utilized linear optics constrained by light diffraction (e.g., λ / 2NA) and could only detect diffracted light from the target when the pitch of the target was at least half the detection wavelength of the measuring light.

[0007] At any small pitch, these prior systems could not accurately measure the diffracted light, thus reaching the diffraction limit for visible light. Prior systems based on linear optics could not perform alignment of diffraction gratings far below the diffraction limit. Furthermore, the reduction in the wavelength of the measured light was limited by the photoresistivity of the resist. The conventional diffraction limit of prior systems could be at pitches of 500 nm or larger. Additionally, alignment marks could be deformed due to wafer processing. When such deformation is asymmetrical, the intensity and phase of the diffracted light can cause significant positional shifts. Summary of the Invention

[0008] Therefore, it is necessary to improve the resolution and accuracy of measuring target position and asymmetry on a substrate, reduce the number of targets and the total area occupied by them, and reduce errors in the photolithography process. Additionally, it would be desirable to detect the subwavelength characteristics of targets (e.g., alignment marks), measure the asymmetry of said targets, and increase the resolution of the sensor device (e.g., by at least four times). To improve such a photolithography process, it is possible to utilize the instantaneous change in the refractive index of the target induced by higher-order nonlinear effects (e.g., second-order effects) in the pump-probe scheme to measure the subwavelength structure. For example, an optical measurement system may include a sensor device that uses nonlinear optical effects to change the refractive index at scales above conventional diffraction limits, thereby enabling the sensor device to obtain information about the position and asymmetry of the subwavelength structure.

[0009] In some aspects, a sensor device may include a transient optical pattern, a probe beam, and a detector. In some aspects, the transient optical pattern may be configured to induce a material change in an alignment mark, thereby forming an effective alignment mark. In some aspects, the probe beam may be configured to interact with the effective alignment mark. In some aspects, the detector may be configured to measure diffracted or reflected light from the effective alignment mark generated by the probe beam.

[0010] In some aspects, the material change may include a change in the refractive index of the alignment marks. In some aspects, the material change may be proportional to the intensity of the transient optical pattern.

[0011] In some aspects, the transient optical pattern may include an interference pattern. In some aspects, the transient optical pattern may originate from multiple deflected beams. In some aspects, the transient optical pattern may be an arbitrary image pattern. For example, the arbitrary image pattern may be a grating pattern, a checkerboard pattern, a finite pattern, or a combination thereof.

[0012] In some aspects, the probe beam can be configured to interact with the effective alignment mark over a time span of material change. In some aspects, the diffracted light can include a first-order diffracted beam (I) from the effective alignment mark. -1 I +1 ).

[0013] In some aspects, the diffracted light can be diffracted from a spatially periodic pattern of the effective alignment mark, the spatially periodic pattern being formed by a combination (e.g., multiplication) of the transient optical pattern and the alignment mark. In some aspects, the spatially periodic pattern may include one or more spatial harmonics of the transient optical pattern. In some aspects, the relative periodicity between the period of the transient optical pattern and the period of the alignment mark increases the resolution of the sensor device as the relative periodicity decreases. In some aspects, the relative periodicity can increase the resolution of the sensor device by at least four times.

[0014] In some aspects, the sensor device may further include a processor coupled to the detector. In some aspects, the processor may be configured to determine the position of the alignment mark based on the asymmetry of the diffracted light.

[0015] In some aspects, the alignment mark may be adjustable relative to the transient optical pattern and the probe beam. In some aspects, the probe beam may be adjustable relative to the alignment mark and the transient optical pattern.

[0016] In some aspects, the sensor device may also include an interferometric measuring device. In some aspects, the interferometric measuring device may be configured to receive diffracted light and interfere with itself to generate an alignment signal. In some aspects, the sensor device may also include a processor coupled to a detector. In some aspects, the processor may be configured to determine the asymmetry of the alignment mark.

[0017] In some aspects, a method may include forming a transient optical pattern on an alignment mark, thereby inducing a material change in the alignment mark and forming an effective alignment mark. In some aspects, the method may further include interacting a probe beam with the effective alignment mark. In some aspects, the method may further include measuring diffracted light from the effective alignment mark generated by the probe beam.

[0018] In some aspects, the method may further include determining the position of the alignment mark based on the asymmetry of the diffracted light. In some aspects, the method may further include determining the asymmetry of the alignment mark based on the asymmetry of the diffracted light.

[0019] In some aspects, the method may further include scanning the alignment mark relative to the instantaneous optical pattern and the probe beam. In some aspects, the method may further include scanning the instantaneous optical pattern relative to the alignment mark and the probe beam. In some aspects, the method may further include scanning the probe beam relative to the alignment mark and the instantaneous optical pattern.

[0020] Implementations of any of the techniques described above may include EUV light sources, DUV light sources, systems, methods, processes, apparatuses, and / or devices. Details of one or more embodiments are set forth in the following drawings and embodiments. Other features will be apparent from the description, drawings, and claims.

[0021] Other features and exemplary aspects of the various aspects, as well as the structure and operation of the various aspects, are described in detail below with reference to the accompanying drawings. It should be noted that the aspects are not limited to the specific aspects described herein. Such aspects are presented herein for illustrative purposes only. Additional aspects will be apparent to those skilled in the art based on the teachings contained herein. Attached Figure Description

[0022] The accompanying drawings, which are incorporated herein and form part of this specification, illustrate various aspects and, together with the embodiments, further serve to explain the principles of the various aspects and enable those skilled in the art to perform and use the aspects.

[0023] Figure 1 This is a schematic diagram of a lithography apparatus according to an exemplary aspect.

[0024] Figure 2 This is a schematic front view of a sensor device that applies a transient optical pattern to an alignment mark to form an effective alignment mark, according to an exemplary aspect.

[0025] Figure 3 Based on exemplary aspects Figure 2 The schematic front view of the sensor device shown is shown, in which the sensor device guides the probe beam at the effective alignment mark.

[0026] Figure 4 It is formed by combining (e.g., multiplying) the alignment marks of the exemplary aspect with the instantaneous optical pattern. Figure 2 The diagram shows a schematic representation of the effective alignment mark.

[0027] Figure 5 Based on exemplary aspects Figure 2 The schematic front view of the sensor device shown guides the probe beam at the periodic pattern of the effective alignment marks.

[0028] Figures 6A to 6C It is based on the exemplary aspects from and Figure 2 A schematic drawing of the diffracted light of the effective alignment mark, showing an exemplary position of the alignment mark.

[0029] Figure 7 It is a schematic drawing relating to the spatial frequency of an instantaneous optical pattern on an alignment mark, based on an exemplary aspect.

[0030] Figure 8 This is a schematic front view of a sensor device for detecting an exemplary diffraction order of a spatial periodic pattern of an effectively aligned mark according to an exemplary aspect.

[0031] Figure 9 This is a schematic diagram of a sensor device external to a lithography apparatus, based on an exemplary aspect.

[0032] Figure 10 It is a schematic diagram of the material change of the asymmetric alignment mark caused by a momentary optical pattern for the exemplary position of the asymmetric alignment mark, according to an exemplary aspect.

[0033] Figure 11A It is a schematic drawing based on an exemplary aspect of the diffraction efficiency of zero-order diffracted light for an instantaneous grating having the same period as the symmetry alignment mark.

[0034] Figure 11B It is based on the exemplary aspect, for having with Figure 10 A schematic drawing illustrating the diffraction efficiency of zero-order diffracted light from an instantaneous grating with the same period, showing asymmetric alignment.

[0035] Figure 12A It is a schematic drawing based on an exemplary aspect of the diffraction efficiency of a first-order diffracted light for an instantaneous grating having the same period as the symmetry alignment mark.

[0036] Figure 12B It is based on the exemplary aspect, for having with Figure 10 A schematic drawing illustrating the diffraction efficiency of the first-order diffracted light of an instantaneous grating with the same period as the asymmetric alignment marks.

[0037] Figure 13A It is a schematic drawing of the diffraction efficiency of second-order diffracted light for an instantaneous grating having the same period as the symmetry alignment mark, based on an exemplary aspect.

[0038] Figure 13B It is based on the exemplary aspect, for having with Figure 10 A schematic drawing of the diffraction efficiency of second-order diffracted light from an instantaneous grating with the same period, showing asymmetric alignment.

[0039] Figure 14 This is a schematic diagram of a sensor device having an interferometric measurement apparatus for detecting diffracted light, according to an exemplary aspect.

[0040] Features and exemplary aspects will become apparent from the embodiments described below in conjunction with the accompanying drawings. Additionally, generally, the leftmost numeral of the reference numeral identifies the first appearance of that reference numeral in the drawing. Unless otherwise indicated, the drawings provided throughout this disclosure should not be construed as being drawn to scale. Detailed Implementation

[0041] This specification discloses one or more aspects incorporating the features of the invention. The disclosed aspects are merely illustrative. The scope of the invention is not limited to the disclosed aspects. The invention is defined by the appended claims.

[0042] The aspects described herein and the references to "an aspect," "aspect," "example aspect," "exemplary aspect," etc., indicate that the described aspect may include a particular feature, structure, or characteristic, but each aspect may not necessarily include the particular feature, structure, or characteristic. Furthermore, such phrases do not necessarily refer to the same aspect. Moreover, when a particular feature, structure, or characteristic is described in conjunction with an aspect, it should be understood that, whether explicitly described or not, achieving such a feature, structure, or characteristic in conjunction with other aspects is within the understanding of someone skilled in the art.

[0043] For ease of description, spatial relative terms such as “below,” “under,” “lower,” “above,” “upper,” and “upper” are used herein to describe the relationship of one element or feature to another, as illustrated in the accompanying drawings. In addition to the orientations depicted in the drawings, the spatial relative terms are also intended to cover different orientations of the device during use or operation. The device may be oriented in other ways (rotated 90 degrees or otherwise), and the spatial relative descriptors used herein will be interpreted accordingly.

[0044] As used herein, the terms “about,” “roughly,” or “approximately” indicate a value of a given quantity that may vary based on a particular technique. Based on a particular technique, the terms “about,” “roughly,” or “approximately” may indicate a value of a given quantity that varies, for example, within 1% to 15% of the value (e.g., ±1%, ±2%, ±5%, ±10%, or ±15% of the value).

[0045] The aspects of this disclosure can be implemented in hardware, firmware, software, or any combination thereof. The aspects of this disclosure can also be implemented as instructions stored on a machine-readable medium, which can be read and executed by one or more processors. A machine-readable medium can include any means for storing or transmitting information in a form that can be read by a machine (e.g., a computing device). For example, a machine-readable medium can include: read-only memory (ROM); random access memory (RAM); disk storage media; optical storage media; flash memory devices; electrical, optical, acoustic, or other forms of propagation signals (e.g., carrier waves, infrared signals, digital signals, etc.); and other media. Additionally, firmware, software, routines, and / or instructions can be described herein as performing certain actions. However, it should be understood that such descriptions are for convenience only, and such actions are actually caused by a computing device, processor, controller, or other means of executing firmware, software, routines, instructions, etc.

[0046] However, before describing such aspects in more detail, it is instructive to present example environments in which aspects of this disclosure can be implemented.

[0047] Exemplary lithography system

[0048] Figure 1 A lithography system including a radiation source SO and a lithography apparatus LA is shown. The radiation source SO is configured to generate EUV and / or DUV radiation beams B and supply the EUV and / or DUV radiation beams B to the lithography apparatus LA. The lithography apparatus LA includes an irradiation system IL, a support structure MT (e.g., mask stage, mask plate stage, mask plate platform) configured to support a pattern forming apparatus MA (e.g., mask, mask plate), a projection system PS, and a substrate stage WT configured to support a substrate W.

[0049] The irradiation system IL is configured to adjust the EUV and / or DUV radiation beam B before it is incident on the pattern forming apparatus MA. Additionally, the irradiation system IL may include a faceted field mirror assembly 10 and a faceted pupil mirror assembly 11. Together, the faceted field mirror assembly 10 and the faceted pupil mirror assembly 11 provide the EUV and / or DUV radiation beam B with a desired cross-sectional shape and a desired intensity distribution. In addition to or in place of the faceted field mirror assembly 10 and the faceted pupil mirror assembly 11, the irradiation system IL may also include other mirrors or devices.

[0050] After such adjustment, the EUV and / or DUV radiation beam B interacts with the patterning apparatus MA. This interaction can be reflective (as shown), which is preferred for EUV radiation. This interaction can also be transmissive, which is preferred for DUV radiation. Due to this interaction, a patterned EUV and / or DUV radiation beam B' is generated. The projection system PS is configured to project the patterned EUV and / or DUV radiation beam B' onto the substrate W. For this purpose, the projection system PS may include a plurality of mirrors 13, 14 configured to project the patterned EUV and / or DUV radiation beam B' onto the substrate W held by the substrate stage WT. The projection system PS may apply a reduction factor to the patterned EUV and / or DUV radiation beam B', thus forming an image with features smaller than the corresponding features on the patterning apparatus MA. For example, a reduction factor of 4 or 8 may be applied. Although the projection system PS in Figure 1 The diagram shows only two mirrors 13 and 14, but the projection system PS can include a different number of mirrors (e.g., six or eight mirrors).

[0051] The substrate W may include a previously formed pattern. In such a case, the photolithography apparatus LA aligns the image formed by the patterned EUV and / or DUV radiation beams B' with the pattern previously formed on the substrate W.

[0052] Exemplary sensor device

[0053] As discussed above, in order to control the photolithography process to accurately form device features on the substrate, one or more diffraction targets (e.g., alignment marks, overlap marks) are placed on the substrate. The photolithography apparatus uses one or more sensors (e.g., alignment sensors, overlap sensors, and / or combinations of both) to accurately measure the characteristics (e.g., position, overlap) of the diffraction targets.

[0054] Existing alignment systems and techniques are subject to certain drawbacks and limitations. For example, previous systems utilized linear optics that could only detect diffracted light when the target pitch was greater than half the detection wavelength of the light. At any smaller pitch, these previous systems could not accurately measure the diffracted light, thus reaching the diffraction limit for visible light. Previous systems using linear optics could not perform alignment of diffraction gratings far below the diffraction limit. The conventional diffraction limit of previous systems could be at pitches of 500 nm or larger. Furthermore, alignment marks can be deformed due to wafer processing. When such deformation is asymmetrical, the intensity and phase of the diffracted light can cause significant positional shifts.

[0055] The sensor devices, systems, and methods discussed below utilize nonlinear effects of target pitches with diffraction limits below the visible light limit, thereby bringing the pitch size closer to the product structure. This pitch can be referred to as a subwavelength pitch. These imaging techniques enable such sensor devices and systems to resolve targets with conventional diffraction limits (e.g., visible light diffraction limits) below optical resolution, thus achieving super-resolution.

[0056] The sensor devices, systems, and methods discussed below can provide resolution and accuracy for measuring target location and target asymmetry on a substrate, reduce the number of targets and the total area occupied by targets, and reduce errors in the photolithography process.

[0057] Figure 2 , Figure 3 and Figure 5 The illustration shows a sensor device 200 according to an exemplary aspect. The sensor device 200 can be configured to illuminate a diffraction target (e.g., alignment mark 206) and detect characteristics of one or more diffraction targets (e.g., alignment position, mark asymmetry, pitch, diffraction order, depth, sub-segmentation, etc.), thereby improving, for example, the alignment and calibration of a photolithography apparatus LA. In some aspects, the sensor device 200 may include a first light source 201, a second light source 212, and a detector 213. In some aspects, the first light source 201 and the second light source 212 may be a single light source (e.g., a broadband light source, a coherent light source, a laser, a laser diode, etc.). Although the sensor device 200 is in... Figure 2 While shown as a standalone device and / or system, aspects of this disclosure may be used in conjunction with other devices, systems, and / or methods, such as lithography equipment LA, sensor device 200', and / or sensor device 200''.

[0058] like Figure 2 , Figure 3 and Figure 5 As shown, the sensor device 200 may include a probe beam 216 (e.g., from a second light source 212) configured to interact with an effective alignment mark 210, which is formed by a transient optical pattern 208 that induces a material change (e.g., a transient change in refractive index) in the alignment mark 206.

[0059] In some aspects, the first light source 201 may be configured to use two or more light guides 202a, 202b (e.g., optical fibers, light pipes, mirrors, beam splitters) configured to guide two or more pump beams 203a, 203b to a lens 205 positioned at a focal length f from the light guides 202a, 202b (e.g., pupil plane). The lens 205 may be positioned at a focal length f from the alignment mark 206 (e.g., object plane). Refraction of the pump beams 203a, 203b through the lens 205 may redirect the pump beams 203a, 203b into deflected beams 204a, 204b at the alignment mark 206. In some aspects, the light guides 202a, 202b may be configured to guide the pump beams 203a, 203b at a deflection angle toward the alignment mark 206 without using the lens 205.

[0060] In some aspects, the first light source 201 can be configured to provide a coherent electromagnetic broadband illumination beam (e.g., pump beams 203a, 203b) having one or more frequency bands. In some aspects, the one or more frequency bands can be within the visible spectrum with wavelengths between about 380 nm and about 750 nm. For example, the wavelength can be in the range of about 450 nm to about 550 nm, for example, about 500 nm. In some aspects, the one or more frequency bands can be within the ultraviolet spectrum with wavelengths between about 100 nm and about 380 nm. For example, the wavelength can be in the range of about 350 nm to about 380 nm, for example, about 365 nm. In some aspects, the one or more frequency bands can be within the infrared spectrum with wavelengths between about 750 nanometers and about 2 micrometers. For example, the wavelength can be in the range of about 750 nm to about 900 nm, for example, about 850 nm.

[0061] In some aspects, the first light source 201 may be a pulsed source. For example, the first light source 201 may have a pulse width within the time range of the nonlinear effect in the alignment mark 206. In some aspects, the pulse width of the first light source 201 may not be greater than 1 μs.

[0062] In some aspects, alignment mark 206 may be a diffraction target. In some aspects, alignment mark 206 may include a diffraction grating. In some aspects, alignment mark 206 may be a 1-D grating, printed such that, after development, the grating strips are formed by solid resist lines. In some aspects, alignment mark 206 may be a 2-D array or a 2-D grating, printed such that, after development, the grating is formed by solid resist grating strips, pillars, or through-holes in the resist. In some aspects, alignment mark 206 may include a target on a substrate to receive pump beams 203a, 203b or deflection beams 204a, 204b. In some aspects, alignment mark 206 may be a grating with a pitch range of about 10 nm to about 100 nm. In some aspects, alignment mark 206 (e.g., a diffraction grating) may include lines and spaces of different materials. In some aspects, the lines of alignment mark 206 may be made of a semiconductor material. For example, the lines of alignment mark 206 may be made of silicon. In some respects, the space of the alignment mark 206 may be composed of a gas. For example, the space of the alignment mark 206 may be composed of air.

[0063] In some aspects, the material of alignment mark 206 can change its refractive index when irradiated by a strong, short laser pulse (e.g., from first light source 201). After absorbing the laser pulse, the change in refractive index of the material (e.g., alignment mark 206) can be proportional to the electric field of the light (e.g., the Pockels effect), proportional to the square of the electric field (e.g., the Kerr effect, thermo-optical effects), or proportional to a higher order (e.g., an nth-order nonlinear effect). For example, the material change of alignment mark 206 attributed to the Kerr effect can be proportional to the intensity of the laser pulse (e.g., from first light source 201), thereby producing an intensity-dependent refractive index n = n0 + n2 I in alignment mark 206 (e.g., effective alignment mark 210). pump Where n0 is the linear refractive index of the material aligned to mark 206, n2 is the second-order nonlinear refractive index, and I pump The intensity of the laser pulse (e.g., from the first light source 201).

[0064] In some aspects, light guides 202a and 202b may be configured to guide a first pump beam 203a and a second pump beam 203b toward a lens 205. In some aspects, light guides 202a and 202b may include any optical device (e.g., a mirror, lens, prism, waveguide, optical modulator, etc.). In some aspects, light guides 202a and 202b may include a beam splitter configured to split an illumination beam from a first light source 201 into a first pump beam 203a and a second pump beam 203b. The first light guide 202a may guide the first pump beam 203a toward the lens 205. The second light guide 202b may guide the second pump beam 203b toward the lens 205. In some aspects, light guides 202a and 202b may be able to change each incident angle of the first pump beam 203a and the second pump beam 203b. In some aspects, lens 205 may have a refractive index and focal length f, such that the first pump beam 203a and the second pump beam 203b can be guided toward alignment mark 206 as two or more deflected beams 204a, 204b. In some aspects, light guides 202a, 202b may be configured to guide pump beams 203a, 203b toward alignment mark 206 at a deflection angle without using lens 205.

[0065] In some aspects, the transient optical pattern 208 may be formed by multiple deflected light beams (e.g., deflected light beams 204a, 204b passing through lens 205 toward alignment mark 206, pump beams 203a, 203b, etc., guided at a deflection angle toward alignment mark 206 without passing through lens 205). In some aspects, the transient optical pattern 208 may be an interference pattern. In some aspects, the transient optical pattern 208 may be any image pattern. For example, the transient optical pattern 208 may be a grating pattern, a checkerboard pattern, a finite pattern, or a combination thereof. In some aspects, the transient optical pattern may have an intensity distribution with a sinusoidal pattern, a triangular pattern, a rectangular pattern, or a combination thereof.

[0066] As discussed above, alignment marks 206 may include gratings (e.g., 1-D gratings), and the lines and spaces of alignment marks 206 may be made of different materials, thus the material variations (e.g., refractive index variations) in the different materials may also have different values. In some aspects, the transient optical pattern 208 can produce refractive index modulation by combining (e.g., multiplying) the distribution of the transient optical pattern 208 with the alignment marks 206. For example, as Figure 4As shown, an effective alignment mark 406 is generated by the interaction (e.g., nonlinear effects) between the alignment mark 402 and the transient optical pattern 404 (e.g., a combination of the transient optical pattern 404 and the alignment mark 402). This modulation can be attributed to various linear and nonlinear effects (e.g., second-order nonlinear effects) resulting in periodic material changes (e.g., refractive index changes) in the alignment mark 206. In some aspects, the combination (e.g., multiplication) of the transient optical pattern 208 and the alignment mark 206 can generate an effective alignment mark 210, characterized by refractive index modulation (e.g., as... Figure 10 As shown in the figure.

[0067] In some aspects, the transient optical pattern 208 may induce a material change in the alignment mark 206, thereby forming an effective alignment mark 210. In some aspects, the material change may be a change in the refractive index of the alignment mark 206. In some aspects, a first deflecting beam 204a may be directed to the alignment mark 206 at a first incident angle, and a second deflecting beam 204b may be directed to the alignment mark 206 at a second incident angle. In some aspects, the first deflecting beam 204a and the second deflecting beam 204b (e.g., coherent light) may be spatially and temporally superimposed to form a grating-like interference pattern (e.g., the transient optical pattern 208). In some aspects, the pitch of the transient optical pattern 208 may be greater than the pitch of the alignment mark 206. For example, the transient optical pattern 208 may have a pitch of about 500 nm, and the alignment mark 206 may have a pitch in the range of about 10 nm to about 300 nm. In some aspects, the pitch of the transient optical pattern 208 may be similar to the pitch of the alignment mark 206. In other aspects, the pitch of the transient optical pattern 208 may be smaller than the pitch of the alignment mark 206. For example, the transient optical pattern 208 may have a pitch of about 100 nm, and the alignment mark 206 may have a pitch of about 200 nm.

[0068] In some aspects, the light source (e.g., the second light source 212) can be configured to guide the probe beam (e.g., Figure 3 The probe beam 216 shown interacts with the effective alignment mark 210 to produce diffracted light (e.g., Figure 3 The diffracted light shown is 218a, 218b. In some aspects, the first light source 201 or the second light source 212 can guide the probe beam. Figure 2 In the exemplary aspect shown, the second light source 212 can guide the probe beam.

[0069] In some aspects, the first light source 201 or the second light source 212 can be configured to guide a probe beam having one or more frequency bands (e.g., Figure 3The detector beam 216 shown is included. In some aspects, one or more frequency bands may be within the visible spectrum with wavelengths between about 380 nm and about 750 nm. For example, the wavelength may be in the range of about 500 nm to about 750 nm, for example, about 700 nm. In some aspects, one or more frequency bands may be within the ultraviolet spectrum with wavelengths between about 100 nm and about 380 nm. For example, the wavelength may be in the range of about 350 nm to about 380 nm, for example, about 365 nm. In some aspects, one or more frequency bands may be within the infrared spectrum with wavelengths between about 750 nanometers and about 2 micrometers. For example, the wavelength may be in the range of about 750 nm to about 1100 nm, for example, about 950 nm. In some aspects, the first wavelength of the first light source 201 may be less than the second wavelength of the second light source 212. In some aspects, the first wavelength of the first light source 201 may be equal to the second wavelength of the second light source 212.

[0070] In some aspects, the second light source 212 may be a pulsed source. In some aspects, the pulse width of the second light source 212 may be within the range of millisecond accuracy, microsecond accuracy, nanosecond accuracy, picosecond accuracy, femtosecond accuracy, or atomic second accuracy. For example, the pulse width may be in the range of about 1 millisecond to about 1 nanosecond, for example, about 100 nanoseconds. For example, the pulse width may be in the range of about 1 microsecond to about 1 picosecond, for example, about 100 picoseconds. For example, the pulse width may be in the range of about 1 microsecond to about 1 femtosecond, for example, about 10 femtoseconds. For example, the pulse width may be in the range of about 1 nanosecond to about 1 atomic second, for example, about 100 atomic seconds. In some aspects, the second light source 212 may have a pulse width less than or equal to the time range (e.g., the time range of the Kerr effect) of the material change (e.g., refractive index change) of the alignment mark 206 induced by the instantaneous optical pattern 208. For example, the pulse width of the second light source 212 may be no greater than (no longer than) 1 microsecond. For example, the pulse width of the second light source 212 may be no greater than (no longer than) 1 nanosecond. For example, the pulse width of the second light source 212 may be no greater than (no longer than) 1 picosecond. For example, the pulse width of the second light source 212 may be no greater than (no longer than) 1 femtosecond. For example, the pulse width of the second light source 212 may be no greater than (no longer than) 1 atomic second.

[0071] In some respects, detector 213 can be configured to measure diffracted light (e.g., Figure 3 The diffracted light 218a, 218b shown makes it possible for a processor coupled to detector 213 to base its signal on the diffracted light from effective alignment mark 210 (e.g., Figure 3 The asymmetry of the diffracted light 218a, 218b shown (e.g., the order diffraction intensity I) -1 I +1The difference between the two points determines the position and / or asymmetry of the alignment mark 206. In some aspects, the detector 213 may be coupled to collecting optics 214a, 214b (e.g., light guides, light pipes, optical fibers, etc.), which are configured to detect diffracted light at the pupil plane of the sensor device 200 (e.g., the difference between the two points). Figure 3 The diffracted light shown is 218a, 218b. In some aspects, the processor can be configured to measure the diffracted light at an angle corresponding to the pitch of the instantaneous optical pattern 208 (e.g., Figure 3 The diffracted light shown is 218a, 218b. In some aspects, detector 213 can be configured to measure the reflected light (e.g., zero-order beam) from effective alignment mark 210.

[0072] Figure 3 Further illustration shows a sensor device 200 according to an exemplary aspect. Figure 2 The above discussion of sensor devices 200 applies to Figure 3 The discussion. Figure 2 The aspects of the sensor device 200 shown are... Figure 3 The aspects of the sensor device 200 shown may be similar. Similar reference figures are used to indicate... Figure 2 Features of the sensor device 200 shown Figure 3 Similar features to aspects of the sensor device 200 shown.

[0073] In some respects, the transient optical pattern 208 can interact with the alignment mark 206 (e.g., light absorption), thereby causing a change in the refractive index of the material of the alignment mark 206. For example, as Figure 3 As shown, the transient optical pattern 208 can generate periodic refractive index modulation by combining (e.g., multiplying) the distribution of the transient optical pattern 208 with the alignment mark 206. In some aspects, the combination (e.g., multiplying) of the transient optical pattern 208 with the alignment mark 206 can generate an effective alignment mark 210, characterized by refractive index modulation.

[0074] In some aspects, a light source (e.g., a second light source 212) can be configured to guide the probe beam 216 to interact with the effective alignment mark 210, thereby generating diffracted light 218a, 218b. In some aspects, the probe beam 216 can interact with the effective alignment mark 210 over a time span (e.g., the time span of the Kerr effect) induced by the transient optical pattern 208. In some aspects, either the first light source 201 or the second light source 212 can guide the probe beam 216. Figure 3In the exemplary aspects shown, the second light source 212 can guide the probe beam 216. In some aspects, the first wavelength of the first light source 201 is less than the second wavelength of the second light source 212. For example, the second light source 212 may have a wavelength of 700 nm and the first light source may have a wavelength of 500 nm. In some aspects, the first wavelength of the first light source 201 may be equal to the second wavelength of the second light source 212. For example, the first light source may have a wavelength of 500 nm and the second light source 212 may have a wavelength of 500 nm.

[0075] In some aspects, the alignment mark 206 may be adjustable relative to the transient optical pattern 208 and the probe beam 216. For example, the alignment mark 206 may be translated along the horizontal axis (Y-axis) relative to the transient optical pattern 208 and the probe beam 216, which can be kept fixed. In some aspects, the transient optical pattern 208 may be adjustable relative to the alignment mark 206 and the probe beam 216. For example, the transient optical pattern 208 may be translated along the horizontal axis (Y-axis) relative to the alignment mark 206 and the probe beam 216, which can be kept fixed (e.g., scanning, rasterization). In some aspects, the probe beam 216 may be adjustable relative to the alignment mark 206 and the transient optical pattern 208. For example, the probe beam 216 may be translated along the horizontal axis (Y-axis) relative to the alignment mark 206 and the transient optical pattern 208, which can be kept fixed (e.g., scanning, rasterization).

[0076] In some respects, the beam of diffracted light can be diffracted from a diffracting target such as the effective alignment mark 210. For example, as Figure 3 As shown, the diffracted light 218 may include a first diffracted light 218a and a second diffracted light 218b. In some aspects, the first diffracted light 218a may be a negative diffraction order beam (e.g., -1), and the second diffracted light 218b may be a positive diffraction order beam (e.g., +1). In some aspects, the diffracted lights 218a and 218b may be higher-order diffracted beams (e.g., a negative second-order beam and a positive second-order beam, a negative third-order beam and a positive third-order beam, etc.). Figure 3 As shown, the first diffracted light 218a and the second diffracted light 218b can be transmitted toward the lens 205 and can be refracted through the lens 205 and redirected toward the collecting optics 214a, 214b connected to the detector 213.

[0077] In some aspects, detector 213 may be coupled to collecting optics 214a, 214b. The collecting optics 214a, 214b (e.g., fixed optics) may be configured to collect diffracted light 218a, 218b in the pupil plane of sensor device 200 and transmit the diffracted light 218a, 218b toward detector 213. Detector 213 may be configured to measure the diffracted light (e.g., diffracted light 218a, 218b) or reflected light (e.g., zero-order beam) and determine the position or asymmetry of alignment mark 206. In some aspects, detector 213 may be coupled to a processor configured to determine the position or asymmetry of alignment mark 206. In some aspects, detector 213 may be configured to measure characteristics of a diffracted target, such as alignment mark 206, based on diffracted light 218a, 218b. In some aspects, the characteristics of a diffracted target, such as alignment mark 206, measured by detector 213 are the alignment position. In some aspects, the characteristic of the diffracted target, such as alignment mark 206, measured by detector 213 is the asymmetry of alignment mark 206. In some aspects, the characteristic of the diffracted target, such as alignment mark 206, measured by detector 213 is overlap. In some aspects, detector 213 can measure diffracted light 218a, 218b at an angle corresponding to the pitch of instantaneous optical pattern 208. In some aspects, detector 213 can be a photodetector, photodiode, charge-connected device (CCD), avalanche photodiode (APD), camera, PIN detector, multimode fiber, single-mode fiber, or any other suitable optical detector.

[0078] Figure 4 The diagram illustrates a pattern 400 of unit cells of an effective alignment mark 406 formed by combining (e.g., multiplying) the unit cells of an alignment mark 402 with a single cycle of an instantaneous optical pattern 404. Figure 4 A graph 400 is shown with an amplitude 408 on the Y-axis and a position 410 on the X-axis.

[0079] In some aspects, alignment mark 402 can be depicted as a unit cell in a graphical representation having an amplitude 408 on the Y-axis and a position 410 on the X-axis. Alignment mark 402 may include a plurality of alignment mark peaks 412 corresponding to material lines of alignment mark 402. In some aspects, the unit cell of alignment mark 402 may include a first alignment mark peak, a second alignment mark peak, a third alignment mark peak, a fourth alignment mark peak, and fifth alignment mark peaks 412a to 412e. Alignment mark 402 may include gaps between alignment mark peaks 412, the gaps corresponding to space in the material of alignment mark 402. The amplitude 408 of the gaps between alignment mark peaks 412 may be zero.

[0080] In some aspects, the transient optical pattern 404 can be depicted as a single period on a graphical representation having an amplitude 408 on the Y-axis and a position 410 on the X-axis. The transient optical pattern 404 may include a transient optical pattern curve 414 spanning the length of the period of the transient optical pattern 404. In some aspects, the transient optical pattern 404 can be any image pattern. For example, the transient optical pattern 404 can be a grating pattern, a checkerboard pattern, a finite pattern, or a combination thereof. In some aspects, the transient optical pattern can have an intensity distribution with a sinusoidal pattern, a triangular pattern, a rectangular pattern, or a combination thereof. Figure 4 In the exemplary aspect shown, the instantaneous optical pattern curve 414 may be a sine pattern.

[0081] In some aspects, the effective alignment mark 406 can be depicted as a unit cell in a graphical representation having an amplitude 408 on the Y-axis and a position 410 on the X-axis. The effective alignment mark 406 can be a combination (e.g., multiplication) of the alignment mark 402 and the transient optical pattern 404, thereby adopting a shape that shares the characteristics of the alignment mark peak 412 and the transient optical pattern curve 414. For example, the effective alignment mark 406 can include a plurality of effective alignment mark peaks 416 corresponding to the material line of the alignment mark 402. The effective alignment mark peaks 416 acquire a curvature that matches the curvature of the transient optical pattern curve 414. In some aspects, the unit cell of the effective alignment mark 406 can include a first effective alignment mark peak, a second effective alignment mark peak, a third effective alignment mark peak, a fourth effective alignment mark peak, and fifth effective alignment mark peaks 416a to 416e. The effective alignment mark 406 can include gaps between the effective alignment mark peaks 416, the gaps corresponding to the space of the material of the alignment mark 402. The amplitude 408 of the gap between the effective alignment marker peaks 416 can be zero, thereby reducing the amplitude 408 of the instantaneous optical pattern curve 414 to zero at those corresponding locations by means of a combination of values ​​(e.g., multiplication).

[0082] Figure 5 Further illustrations are provided based on some aspects of sensor device 200. For Figure 2 and Figure 3 The above discussion of sensor devices 200 applies to Figure 5 The discussion. Figure 2 and Figure 3 The aspects of the sensor device 200 shown are... Figure 5 The aspects of the sensor device 200 shown may be similar. Similar reference figures are used to indicate... Figure 2 and Figure 3 Features of the sensor device 200 shown Figure 5 Similar features to aspects of the sensor device 200 shown. Figure 5The illustration shows a visualization of the repeating pattern used for effective alignment of marker 210, and... Figure 4 The graphic illustration of the effective alignment mark 406 shown is similar.

[0083] In some respects, the effective alignment mark 210 can be considered as a repeating periodic pattern 209 of the effective alignment mark peaks 416a to 416n of the unit cell of the effective alignment mark 406, such as Figure 4 As shown, the effective alignment mark 210 may include a first effective alignment mark peak to an nth effective alignment mark peak 416a to 416n, where n is an integer greater than 1. The effective alignment mark peaks 416a to 416n may correspond to... Figure 2 and Figure 3 The material line of alignment mark 206 shown. The gap between the effective alignment mark peaks 416a to 416n can correspond to Figure 2 and Figure 3 The material space of the alignment mark 206 shown. In some aspects, each of the effective alignment mark peaks 416a to 416n may have a pitch ranging from about 10 nm to about 100 nm. In some aspects, the effective alignment mark 210 may include a first periodic pattern to an nth periodic pattern 209a to 209n, where n is an integer greater than 1. The periodic patterns 209a to 209n can be considered as repeating patterns of unit cells of the effective alignment mark 406, such as Figure 4 As shown in the illustration. In some aspects, the periodic pattern 209 (e.g., periodic pattern 209a) may include a plurality of effective alignment mark peaks 416a to 416n (e.g., effective alignment mark peaks 416a to 416d). In some aspects, each periodic pattern 209a to 209n may have a pitch of about 500 nm.

[0084] Figures 6A to 6C The illustrations are plots 600a, 600b, 600c of diffracted light (e.g., diffraction intensities 614a to 614c, 616a to 616c) from the effective alignment mark 606, which are formed by combining (e.g., multiplying) the unit cell of the alignment mark 602 with a single period of the instantaneous optical pattern 604 according to exemplary aspects. Figures 6A to 6C Graphs 600a, 600b, and 600c show diffracted light from effective alignment mark 606 coinciding with exemplary positions 610 (e.g., 0, p / 4, p / 2) of alignment mark 602, where amplitude 608 is on the Y-axis and position 610 is on the X-axis. Pitch p represents the period of alignment mark 602 and can be the distance between the peaks of alignment mark 602.

[0085] In some aspects, the probe beam 612 can be directed toward effective alignment marks 606a to 606c, respectively, to produce negative diffraction intensities 614a to 614c and positive diffraction intensities 616a to 616c, respectively. The detector (e.g., Figure 5 The detector 213 shown can measure the asymmetry in the intensity of negative diffracted light 614a to 614c and positive diffracted light 616a to 616c, respectively. For example, the detector (e.g., Figure 5 The detector 213 shown can measure the asymmetry between the intensity of the negative diffracted light 614a and the intensity of the positive diffracted light 616a. The asymmetry between the intensity of the negative diffracted light 614a to 614c and the intensity of the positive diffracted light 616a to 616c can be based on changes in the linear or spatial reactivity of the material of the alignment mark 602, respectively. In some aspects, for example, if the linear and spatial refractive indices of the material of the alignment mark 602 have different linear or nonlinear refractive indices, mark position information and / or mark asymmetry information can be extracted separately from the diffraction efficiency. The asymmetry between the intensity of the negative diffracted light 614a to 614c and the intensity of the positive diffracted light 616a to 616c can oscillate periodically corresponding to the period of the pitch p of the alignment mark 602, respectively. Therefore, for alignment purposes, a sensor device (e.g., sensor device 200) can detect the position and / or asymmetry of the alignment mark 602.

[0086] In some respects, the position of the alignment mark 602 can vary relative to the instantaneous optical pattern 604 over a period ranging from 0 to p, where p is the pitch of the alignment mark 602. Figures 6A to 6C As seen in the three exemplary aspects, the position of the alignment mark 602 can vary relative to the instantaneous optical pattern 604 within a period ranging from 0 to p / 2. For example, as Figure 6A The drawing 600a of the unit cell of the single-cycle alignment mark 602a with the instantaneous optical pattern 604a at the position X=0, as shown, can form the unit cell of the effective alignment mark 606a. For example, as Figure 6B The drawing 600b of the unit cell of the single-cycle alignment mark 602b with the instantaneous optical pattern 604b at the position X=p / 4, as shown, can form the unit cell of the effective alignment mark 606b. For example, as Figure 6C As shown, the drawing 600c of the unit cell of the single-cycle alignment mark 602c with the instantaneous optical pattern 604c at the position X=p / 2 can form the unit cell of the effective alignment mark 606c.

[0087] In some aspects, plot 600a can represent the position X=0, which begins with the period of the pitch p of alignment mark 602a. The beginning of the material space of alignment mark 602a can be located at the position X=0. This material space of alignment mark 602a can coincide with the peak of transient optical pattern 604a to form effective alignment mark 606a. Probe beam 612 can be directed toward effective alignment mark 606a to generate negative diffraction light 614a and positive diffraction light 616a. At the position X=0, due to the refractive index modulation of alignment mark 602a, the intensity of negative diffraction light 614a can be greater than the intensity of positive diffraction light 616a, thereby creating an asymmetry between negative diffraction light 614a and positive diffraction light 616a. Sensor device (e.g., sensor device 200) can detect this asymmetry, and therefore detect the position X=0 of alignment mark 602a at this position 610.

[0088] In some aspects, plot 600b can represent the position X=p / 4, which is the first quarter of the period of the pitch p of the alignment mark 602b. The middle of the material space of the alignment mark 602b can be located at the position X=p / 4. This material space of the alignment mark 602b can coincide with the peak of the transient optical pattern 604b to form an effective alignment mark 606b. The probe beam 612 can be directed toward the effective alignment mark 606b to generate negative-order diffraction light 614b and positive-order diffraction light 616b. At the position X=p / 4, due to the refractive index modulation of the alignment mark 602b, the intensity of the negative-order diffraction light 614b can be equal to the intensity of the positive-order diffraction light 616b, thereby creating a symmetry between the negative-order diffraction light 614b and the positive-order diffraction light 616b. A sensor device (e.g., sensor device 200) can detect this symmetry, and thus detect the position X=p / 4 of the alignment mark 602b at this position 610.

[0089] In some aspects, plot 600c can represent the position X=p / 2, which is the first half of the period of the pitch p of the alignment mark 602c. The start of the material line of the alignment mark 602c can be located at the position X=p / 2. This material line of the alignment mark 602c can coincide with the peak of the transient optical pattern 604c to form an effective alignment mark 606c. The probe beam 612 can be directed toward the effective alignment mark 606c to generate negative-order diffraction light 614c and positive-order diffraction light 616c. At the position X=p / 2, due to the refractive index modulation of the alignment mark 602c, the intensity of the negative-order diffraction light 614c can be greater than the intensity of the positive-order diffraction light 616c, thereby creating an asymmetry between the negative-order diffraction light 614c and the positive-order diffraction light 616c. A sensor device (e.g., sensor device 200) can detect this asymmetry and thus detect the position of the alignment mark 602c at position 610, where X=p / 2.

[0090] Figure 7 The illustration is based on some aspects of drawing 700 (e.g., Fourier transform), which shows the spatial frequency of the sensor device. Figure 7 A plot 700 is shown where amplitude 702 is on the Y-axis and spatial frequency 704 is on the X-axis. In some aspects, the diffraction limitation of visible light 706 can separate visible spatial frequencies (e.g., the region to the left of the diffraction limitation of visible light 706) from invisible spatial frequencies (e.g., the region to the right of the diffraction limitation of visible light 706) for optical detection. Alignment mark frequency 708 (e.g., alignment mark 206) can be located in the invisible region to the right of the diffraction limitation of visible light 706. Subwavelength alignment marks (e.g., alignment mark 206) can be optically excited by a transient optical pattern (e.g., transient optical pattern 208) to produce interference in the optically detectable visible region to the left of the diffraction limitation of visible light 706. For example, transient optical pattern frequency 710 can be located in the visible region to the left of the diffraction limitation of visible light 706. In some aspects, the first pitch of the transient optical pattern (e.g., transient optical pattern 208) is greater than the second pitch of the subwavelength alignment mark (e.g., alignment mark 206).

[0091] In some aspects, the combination (e.g., multiplication) of a subwavelength alignment mark (e.g., alignment mark 206) with a transient optical pattern (e.g., transient optical pattern 208) can be attributed to higher-order nonlinear effects to generate new spatial frequencies. In some aspects, one or more of the new spatial frequencies can be detected by visible light. In some aspects, the interaction between the transient optical pattern frequency 710 and the alignment mark frequency 708 can generate additional spatial frequencies, such as a first-order difference spatial frequency 714 and a first-order sum spatial frequency 716. The first-order difference spatial frequency 714 and the first-order sum spatial frequency 716 can be located in the non-visible region to the right of the diffraction limit of visible light 706. In some aspects, the transient optical pattern frequency 710 can generate a harmonic spatial frequency 712. The harmonic spatial frequency 712 can be located in the non-visible region to the right of the diffraction limit of visible light 706. In some aspects, the interaction between the harmonic spatial frequency 712 and the alignment mark frequency 708 can generate additional spatial frequencies, such as a second-order difference spatial frequency 718 and a second-order sum spatial frequency 720. The second-order difference spatial frequency 718 can be located in the visible region to the left of the diffraction limit of visible light 706. The second-order sum spatial frequency 720 can be located in the non-visible region to the right of the diffraction limit of visible light 706.

[0092] In some aspects, the diffracted light can be a spatially periodic pattern of effective alignment marks (e.g., effective alignment mark 210) formed by a combination (e.g., multiplication) of a transient optical pattern (e.g., transient optical pattern 208) and an alignment mark (e.g., alignment mark 206). The spatially periodic pattern can include one or more spatial harmonics of the transient optical pattern (e.g., transient optical pattern 208). In some aspects, the processor can measure the diffraction signal from the spatially periodic pattern. Therefore, the diffraction signal from a new spatial frequency (e.g., harmonic spatial frequency 712 and second-order difference spatial frequency 718) can indicate points in the spatially periodic pattern, and thus indicate the position and / or asymmetry of the alignment mark (e.g., alignment mark 206).

[0093] In some aspects, the resolution increases as the relative periodicity between the period of the instantaneous optical pattern and the period of the alignment mark decreases. This increased resolution can be achieved by reducing the minimum pitch of the subwavelength alignment mark (e.g., alignment mark 206). In some aspects, in linear pumping and probing processes involving single-photon transitions, a resolution improvement of √2 can be expected compared to resolution achieved by linear optical microscopy at the same wavelength. For example, measurements based on the harmonic space frequency 712 can be performed by reducing the minimum pitch of the subwavelength alignment mark (e.g., alignment mark 206) by at least a factor of 2, i.e., to at least half. In some aspects, the resolution can be improved by up to √n when an nth-order nonlinearity is used for imaging. For example, imaging utilizing second-order nonlinear effects can improve the resolution to √2. Measurements based on the second-order difference space frequency 718 can be performed by reducing the minimum pitch of the subwavelength alignment mark (e.g., alignment mark 206) by at least a factor of 2, thereby producing a total resolution improvement of at least 4 times in pump-probe schemes using imaging utilizing second-order nonlinear effects.

[0094] Figure 8 The illustration is based on some aspects of sensor equipment 200'. Figure 2 and Figure 3 The above discussion of the sensor device 200 shown applies to Figure 8 The sensor device 200' shown is illustrated. Figure 2 , Figure 3 and Figure 5 The aspects of the sensor device 200 shown are... Figure 8 The aspects of the sensor device 200' shown may be similar. Similar reference figures are used to indicate... Figure 2 , Figure 3 and Figure 5 Features of the sensor device 200 shown Figure 8 Similar features to aspects of the sensor device 200' shown. For example... Figure 8 As shown, sensor device 200' can detect spatially diffracted light 220a, 220b from a spatially periodic pattern (e.g., different diffraction waves) of effective alignment mark 210, rather than detecting light from... Figure 2 , Figure 3 and Figure 5 The diffracted light 218a, 218b of the effective alignment mark 210 of the sensor device 200 shown (e.g., first-order diffraction at an angle corresponding to the pitch of the instantaneous optical pattern 208). Sensor device 200' may be an alternative aspect of sensor device 200, wherein sensor device 200' may include higher-order collecting optics 215a, 215b (e.g., diffraction angles corresponding to spatial periodic patterns).

[0095] In some aspects, the light source can be configured to guide the probe beam 216 at the effective alignment mark 210 to produce spatially diffracted light 220a, 220b (as described above regarding...). Figure 7 (As discussed). In some aspects, the first light source 201 or the second light source 212 can guide the probe beam 216. Figure 8 In the exemplary aspects shown, the second light source 212 can guide the probe beam 216. In some aspects, the detector 213 can be configured to receive spatially diffracted light 220a, 220b by means of higher-order collecting optics 215a, 215b instead of collecting optics 214a, 214b, such that the sensor device 200' can measure the position and / or asymmetry of the alignment mark 206 based on the asymmetry of the spatially diffracted light 220a, 220b from the spatially periodic pattern of the effective alignment mark 210.

[0096] In some aspects, the spatially diffracted beams 220a and 220b may be a spatially periodic pattern of the effective alignment mark 210. In some aspects, the spatially periodic pattern may include the nth harmonic spatial frequency of the frequency of the transient optical pattern 208, where n is an integer greater than 1. For example, components of the spatially diffracted beams 220a and 220b may be the second harmonic spatial frequency of the transient optical pattern 208. In some aspects, the interaction between the nth harmonic spatial frequency of the frequency of the transient optical pattern 208 (e.g., harmonic spatial frequency 712) and the frequency of the alignment mark 206 (e.g., alignment mark frequency 708) may generate additional spatial frequencies, such as sum spatial frequencies (e.g., second-order sum spatial frequency 720) and difference spatial frequencies (e.g., second-order difference spatial frequency 718). In some aspects, the additional spatial frequencies may be visible or invisible. For example, the difference spatial frequency (e.g., second-order difference spatial frequency 718) may be in the visible spectrum.

[0097] In some aspects, the resolution increases as the relative periodicity between the period of the instantaneous optical pattern 208 and the period of the alignment mark 206 decreases. This increased resolution can be achieved by reducing the minimum pitch of the alignment mark 206. In some aspects, in linear pumping and probing processes involving single-photon transitions, a resolution improvement of √2 is expected compared to that achieved by linear optical microscopy at the same wavelength. For example, the measurement of the second harmonic space frequency (e.g., harmonic space frequency 712) based on the frequency of the instantaneous optical pattern 208 can be achieved by reducing the minimum pitch of the alignment mark 206 by at least two times.

[0098] In some respects, when an nth-order nonlinearity is used for imaging, the resolution can be improved by up to √n. For example, imaging using a second-order nonlinear effect can improve the resolution by √2. Measurements based on the difference spatial frequency (e.g., the second-order difference spatial frequency 718) can reduce the minimum pitch of the alignment mark 206 by at least 2 times, thereby producing an overall resolution improvement of at least 4 times in pump-probe schemes using imaging with a second-order nonlinear effect.

[0099] Figure 9 This is a schematic diagram of a sensor device 200'' connected to a lithography apparatus LA, according to some aspects. In some aspects, the sensor device 200'' may be external to and connected to the lithography apparatus LA. In some aspects, the sensor device 200'' may be either sensor device 200 or 200'. In some aspects, the sensor device 200'' may be used as a reference and / or calibration tool for alignment processes performed on the lithography apparatus LA. For example, slow but accurate measurements can be performed using the disclosed nonlinear techniques with the sensor device 200'', followed by rapid alignment via the lithography apparatus LA. Nonlinear optical sensor data from the sensor device 200'' can be used to calibrate and reference the lithography apparatus LA because the nonlinear techniques used by the sensor device 200'' are sensitive to mark asymmetry and minor defects in alignment marks.

[0100] Figure 10 The illustration illustrates a material change in an alignment mark occurring within sensor device 200, based on several aspects. In some aspects, the material change of the alignment mark can be triggered by a transient optical pattern. In some aspects, the material of the alignment mark can have a linear refractive index n0. In some aspects, the alignment mark can be alignment mark 206 (as discussed above) or asymmetric alignment mark 207. In some aspects, asymmetric alignment mark 207 can be a "ridge" shape with a surface tilt of variable steepness. Figure 10 In one of the exemplary aspects, the asymmetric alignment mark 207 having a "ridge" shape may have a total height of 120 nm and a tilt height of 10 nm.

[0101] exist Figure 10In an exemplary aspect, the material of the asymmetric alignment mark 207 can change its refractive index when irradiated with a transient optical pattern 208 from a light source (e.g., a first light source 201). After absorbing the transient optical pattern 208, the change in refractive index can be proportional to the electric field (e.g., the Pockels effect), proportional to the square of the electric field (e.g., the Kerr effect, thermo-optical effects), or proportional to a higher order (e.g., an nth-order nonlinear effect). For example, the Kerr effect changes the refractive index of the material of the asymmetric alignment mark 207, which is proportional to the intensity of the incident laser pulse from the light source, such that the intensity-dependent refractive index is n = n0 + n2I. pump , where n0 is the linear refractive index of the material with asymmetric alignment mark 207, n2 is the second-order nonlinear refractive index, and I pump The intensity of the laser pulse from the light source.

[0102] In some aspects, the processor can detect information about the position and / or asymmetry of the asymmetric alignment mark 207 based on the location of material change (e.g., refractive index change). As discussed above, the pitch p can be the distance between the peaks of an alignment mark such as the asymmetric alignment mark 207. At position X = -p / 2, the transient optical pattern 208 can occupy the space between the asymmetric alignment marks 207 without causing a change in the refractive index of the asymmetric alignment mark 207. At position X = -p / 4, the transient optical pattern 208 can illuminate a portion of the asymmetric alignment mark 207, thereby inducing an intensity-dependent refractive index n only in the illuminated portion of the asymmetric alignment mark 207, and forming an effective alignment mark 210 in said portion of the asymmetric alignment mark 207. At position X=0, the instantaneous optical pattern 208 can illuminate the entire asymmetric alignment mark 207, thereby inducing an intensity-dependent refractive index n throughout the entire portion of the asymmetric alignment mark 207, and forming an effective alignment mark 210 throughout the entire portion of the asymmetric alignment mark 207. At position X=p / 4, the instantaneous optical pattern 208 can illuminate a portion of the asymmetric alignment mark 207, thereby inducing an intensity-dependent refractive index n only in the illuminated portion of the asymmetric alignment mark 207, and forming an effective alignment mark 210 in said portion of the asymmetric alignment mark 207. At position X=p / 2, the instantaneous optical pattern 208 can occupy the space between the asymmetric alignment marks 207, thereby not causing a change in the refractive index of the asymmetric alignment mark 207.

[0103] Figures 11A to 13B The illustration shows how sub-diffraction imaging can detect alignment mark asymmetry and how it can help distinguish the offset caused by the asymmetry from the actual offset of the alignment mark position. Figures 11A to 13BA shallow grating approximation is used to calculate the signal intensity of the diffracted light. The shallow grating approximation means that the reflected wavefront from the alignment mark is approximated by the distribution of a grating scaled according to the optical path difference. The shallow grating approximation can be used to model the diffraction efficiency using two phase gratings with refractive indices n0 and n and their distributions.

[0104] and

[0105] .

[0106] The reflection coefficient is determined by The constraints are defined, where Δn0 = n0 - 1 and Δn0 = Δn0 + n2, where I is the refractive index difference between the nominal region and the irradiated region relative to the grating space. This can be achieved through... Calculate the diffraction order, where This type of integral can be obtained by using... (exist In the case of) conducting an assessment, and targeting The assessment should be conducted in a similar manner to other situations.

[0107] Figure 11A and Figure 11B The diagram illustrates the zero-order diffraction efficiency 1100 based on several aspects. The zero-order diffraction efficiency 1100 is plotted graphically, showing the variation of the diffraction intensity 1102 on the Y-axis with respect to the instantaneous optical pattern position 1104 on the X-axis. The instantaneous optical pattern position 1104 can be described in micrometers. A constant diffraction intensity 1106 can illustrate the absence of a Kerr effect on the refractive index of the alignment grating. The diffraction intensity curve 1108 can illustrate how the diffraction intensity 1102 varies with the instantaneous optical pattern position 1104 under conditions where the Kerr effect alters the refractive index of the alignment grating.

[0108] Figure 11A The illustration shows the zero-order diffraction efficiency 1100a of diffracted light from a binary grating (e.g., alignment mark 206) according to some aspects. In some aspects, the binary grating (e.g., alignment mark 206) may have a height of 120 nm. In some aspects, the probe beam (e.g., probe beam 216) may have a wavelength of 633 nm. In such a configuration, the binary grating, which is symmetrically shaped, can form a symmetrical signal along the diffraction intensity curve 1108a relative to the alignment instantaneous optical pattern position 1104, which is 0. Therefore, if the alignment mark deviates from the plotted zero-order diffraction efficiency 1100a, the processor can determine the asymmetry of the alignment mark.

[0109] Figure 11BThe illustration shows the zero-order diffraction efficiency 1100b of diffracted light from a ridge-top grating (e.g., asymmetric alignment mark 207) according to some aspects. In some aspects, the ridge-top grating (e.g., asymmetric alignment mark 207) may have a total height of 120 nm and a tilt height of 10 nm. In some aspects, the probe beam (e.g., probe beam 216) may have a wavelength of 633 nm. In such a configuration, the ridge-top grating, in an asymmetric grating shape, can form an asymmetric signal along the diffraction intensity curve 1108b relative to the alignment instantaneous optical pattern position 1104, which is 0. Figure 11B As seen, the kink occurs at this alignment position. Therefore, the zero-order diffraction efficiency 1100b can become positionally dependent on the asymmetric grating. Thus, if the alignment mark deviates from the drawn zero-order diffraction efficiency 1100b, the processor can determine the asymmetry of the alignment mark.

[0110] Figure 12A and Figure 12B The diagram illustrates the first-order diffraction efficiency 1200 based on several aspects. The first-order diffraction efficiency 1200 is plotted graphically, showing the variation of the diffraction intensity 1202 on the Y-axis with respect to the instantaneous optical pattern position 1204 on the X-axis. The instantaneous optical pattern position 1204 can be described in micrometers. A constant diffraction intensity 1206 illustrates the absence of a Kerr effect on the refractive index of the alignment grating. Positive-order diffraction intensity curve 1208 and negative-order diffraction intensity curve 1210 illustrate how the diffraction intensity 1202 varies with the instantaneous optical pattern position 1204 under conditions where the Kerr effect alters the refractive index of the alignment grating.

[0111] Figure 12A The illustration shows the first-order diffraction efficiency 1200a of the diffracted light from a binary grating (e.g., alignment mark 206) according to some aspects. In some aspects, the binary grating (e.g., alignment mark 206) may have a height of 120 nm. In some aspects, the probe beam (e.g., probe beam 216) may have a wavelength of 633 nm. In such a configuration, the binary grating, which is in a symmetrical grating shape, can form an antisymmetric signal between the positive-order diffraction intensity curve 1208a and the negative-order diffraction intensity curve 1210a relative to the alignment instantaneous optical pattern position 1204, which is 0. Figure 12A As seen, the positive diffraction intensity curve 1208a and the negative diffraction intensity curve 1210a intersect at this alignment position. Therefore, the first-order diffraction efficiency 1200a can become positionally dependent on the symmetry grating. Thus, if the alignment mark deviates from the plotted first-order diffraction efficiency 1200a, the processor can determine the asymmetry of the alignment mark.

[0112] Figure 12BThe illustration shows the first-order diffraction efficiency 1200b of the diffracted light from a ridge-top grating (e.g., asymmetric alignment mark 207) according to some aspects. In some aspects, the ridge-top grating (e.g., asymmetric alignment mark 207) may have a total height of 120 nm and a tilt height of 10 nm. In some aspects, the probe beam (e.g., probe beam 216) may have a wavelength of 633 nm. In such a configuration, the ridge-top grating, in an asymmetric grating shape, can form an asymmetric signal between the positive-order diffraction intensity curve 1208b and the negative-order diffraction intensity curve 1210b relative to the alignment instantaneous optical pattern position 1204, which is 0. Figure 12B As seen, a kink occurs at this alignment position. Therefore, the first-order diffraction efficiency 1200b can become position-dependent with respect to the asymmetric grating. Thus, if the alignment mark deviates from the drawn first-order diffraction efficiency 1200b, the processor can determine the asymmetry of the alignment mark.

[0113] Figure 13A and Figure 13B The diagram illustrates the second-order diffraction efficiency 1300 in several aspects. The second-order diffraction efficiency 1300 is plotted graphically, showing the variation of the diffraction intensity 1302 on the Y-axis with respect to the instantaneous optical pattern position 1304 on the X-axis. The instantaneous optical pattern position 1304 can be depicted in micrometers. A constant diffraction intensity 1306 illustrates the absence of a Kerr effect on the refractive index of the alignment grating. Positive second-order diffraction intensity curve 1308 and negative second-order diffraction intensity curve 1310 illustrate how the diffraction intensity 1302 varies with the instantaneous optical pattern position 1304 under conditions where the Kerr effect alters the refractive index of the alignment grating.

[0114] Figure 13A The illustration shows the second-order diffraction efficiency 1300a of diffracted light from a binary grating (e.g., alignment mark 206) according to some aspects. In some aspects, the binary grating (e.g., alignment mark 206) may have a height of 120 nm. In some aspects, the probe beam (e.g., probe beam 216) may have a wavelength of 633 nm. In such a configuration, the binary grating, which is symmetrically shaped, can form a symmetrical signal between the positive second-order diffraction intensity curve 1308a and the negative second-order diffraction intensity curve 1310a relative to the alignment instantaneous optical pattern position 1304, which is 0. Therefore, if the alignment mark deviates from the plotted second-order diffraction efficiency 1300a, the processor can determine the asymmetry of the alignment mark.

[0115] Figure 13BThe illustration shows the second-order diffraction efficiency 1300b of diffracted light from a ridge-top grating (e.g., asymmetric alignment mark 207) according to some aspects. In some aspects, the ridge-top grating (e.g., asymmetric alignment mark 207) may have a total height of 120 nm and a tilt height of 10 nm. In some aspects, the probe beam (e.g., probe beam 216) may have a wavelength of 633 nm. In such a configuration, the ridge-top grating, in an asymmetric grating shape, can form an asymmetric signal between the positive second-order diffraction intensity curve 1308b and the negative second-order diffraction intensity curve 1310b relative to the alignment instantaneous optical pattern position 1304, which is 0. Figure 13B As seen, a kink occurs at this alignment position. Therefore, the second-order diffraction efficiency 1300b can become positionally dependent on the asymmetric grating. Thus, if the alignment mark deviates from the drawn second-order diffraction efficiency 1300b, the processor can determine the asymmetry of the alignment mark.

[0116] Figure 14 The illustration is based on some aspects of sensor equipment 200'''. (For) Figure 2 , Figure 3 and Figure 5 The sensor device 200 shown and Figure 8 The above discussion of sensor devices 200' applies to Figure 14 The sensor device in the middle is 200'''. For example, Figure 2 , Figure 3 and Figure 5 Aspects of the sensor device 200 shown and Figure 8 The aspects of the sensor device 200' shown can be related to Figure 14 The sensor device 200''' shown is similar in aspect. Similar reference numerals are used to indicate... Figure 2 , Figure 3 and Figure 5 Features of the sensor device 200 shown and Figure 8 The features of the sensor device 200' shown are related to... Figure 14 The sensor device 200''' shown has similar features. Sensor device 200''' can be an alternative aspect of sensor device 200 and / or 200', wherein sensor device 200''' may include an interferometric measuring device (e.g., interferometric measuring device 222) that can receive diffracted light and interfere with itself to generate an alignment signal.

[0117] In some aspects, the first light source 201 ( Figure 2 , Figure 3 , Figure 5 and Figure 8The light guides shown can be configured to use two or more light guides 202a, 202b (shown in the diagram). Figure 2 , Figure 3 , Figure 5 and Figure 8 The probe beam 216 is configured to guide multiple deflected beams toward the alignment mark 206 (e.g., deflected beams 204a, 204b that pass through lens 205 toward the alignment mark 206, pump beams 203a, 203b that are deflected at an angle toward the alignment mark 206 without passing through lens 205, etc.). In some aspects, the second light source 212 directs the probe beam 216 at an optical device 217 (e.g., a mirror, lens, prism, waveguide, optical modulator, etc.) to redirect the probe beam 216 toward the alignment mark 206. In some aspects, the probe beam 216 may interact with the effective alignment mark 210 to generate diffracted beams 221a, 221b. In some aspects, the diffracted beams 221a, 221b may be... Figure 3 and Figure 5 The diffracted light shown is 218a, 218b or Figure 8 The spatial diffracted light 220a and 220b shown are illustrated.

[0118] In some aspects, the interferometric measuring device 222 can be configured to receive diffracted light 221a, 221b. In some aspects, the interferometric measuring device 222 can output a modified beam of the received diffracted light 221a, 221b having relative rotation and superposition, thereby interfering the beam of diffracted light 221a, 221b to form transformed diffracted light 224a, 224b. In some aspects, the interferometric measuring device 222 can guide the transformed diffracted light 224a, 224b toward an optical device 223 (e.g., a mirror, lens, prism, waveguide, optical modulator, etc.) to redirect the transformed diffracted light 224a, 224b toward a lens 226. In some aspects, the lens 226 can be positioned at a distance f from the detector 213 (e.g., at the image plane). In some aspects, the lens 226 can guide the transformed diffracted light 224a, 224b toward the detector 213.

[0119] The embodiments can be further described using the following aspects:

[0120] 1. A sensor device, comprising:

[0121] A transient optical pattern, configured to induce a material change in an alignment mark, thereby forming an effective alignment mark;

[0122] The probe beam is configured to interact with the effective alignment mark; and

[0123] A detector configured to measure diffracted or reflected light from the effective alignment mark generated by the probe beam.

[0124] 2. The sensor device according to aspect 1, wherein the material change includes a change in the refractive index of the alignment mark.

[0125] 3. The sensor device according to aspect 1, wherein the material change is proportional to the intensity of the instantaneous optical pattern.

[0126] 4. The sensor device according to aspect 1, wherein the instantaneous optical pattern comprises an interference pattern.

[0127] 5. The sensor device according to aspect 1, wherein the instantaneous optical pattern originates from a plurality of deflected light beams.

[0128] 6. The sensor device according to aspect 1, wherein the instantaneous optical pattern includes arbitrary image patterns, grating patterns, checkerboard patterns, finite patterns, or combinations thereof.

[0129] 7. The sensor device according to aspect 1, wherein the probe beam is configured to interact with the effective alignment mark within the time range of the material change.

[0130] 8. The sensor device according to aspect 1, wherein the diffracted light comprises a first-order diffracted beam (I) from the effective alignment mark. -1 I +1 ).

[0131] 9. The sensor device according to aspect 1, wherein the diffracted light is diffracted from a spatial periodic pattern of the effective alignment mark, the spatial periodic pattern being formed by a combination of the instantaneous optical pattern and the alignment mark.

[0132] 10. The sensor device according to aspect 9, wherein the spatial periodic pattern comprises one or more spatial harmonics of the instantaneous optical pattern.

[0133] 11. The sensor device according to aspect 10, wherein the resolution of the sensor device increases as the relative periodicity between the period of the instantaneous optical pattern and the period of the alignment mark decreases.

[0134] 12. The sensor device according to aspect 11, wherein the relative periodicity increases the resolution of the sensor device by at least 4 times.

[0135] 13. The sensor device according to aspect 1 further includes a processor coupled to the detector and configured to determine the position of the alignment mark based on the asymmetry of the diffracted light.

[0136] 14. The sensor device according to aspect 1, wherein:

[0137] The alignment mark is adjustable relative to the instantaneous optical pattern and the probe beam.

[0138] The instantaneous optical pattern can be adjusted relative to the alignment mark and the probe beam, or

[0139] The probe beam can be adjusted relative to the alignment mark and the instantaneous optical pattern.

[0140] 15. The sensor device according to aspect 1 further includes an interferometric measuring device configured to receive the diffracted light and cause the diffracted light to interfere with itself to generate an alignment signal.

[0141] 16. The sensor device according to aspect 1 further includes a processor coupled to the detector and configured to determine the asymmetry of the alignment mark.

[0142] 17. A method comprising:

[0143] A transient optical pattern is formed on the alignment mark, thereby causing a change in the material of the alignment mark and forming an effective alignment mark;

[0144] The probe beam interacts with the effective alignment mark; and

[0145] Measure the diffracted light from the effective alignment mark generated by the probe beam.

[0146] 18. The method according to aspect 17 further includes determining the position of the alignment mark based on the asymmetry of the diffracted light.

[0147] 19. The method according to aspect 17 further includes determining the asymmetry of the alignment mark based on the asymmetry of the diffracted light.

[0148] 20. The method according to aspect 17 further includes scanning:

[0149] The alignment mark relative to the instantaneous optical pattern and the probe beam,

[0150] The instantaneous optical pattern relative to the alignment mark and the probe beam, or

[0151] The probe beam relative to the alignment mark and the instantaneous optical pattern.

[0152] While specific references may be made herein to the use of lithography equipment in IC manufacturing, it should be understood that the lithography equipment described herein may have other applications, such as manufacturing integrated optical systems, guiding and detecting patterns for magnetic domain memory, flat panel displays, LCDs, thin-film magnetic heads, etc. Those skilled in the art will understand that in the context of such alternative applications, any use of the terms "wafer" or "die" herein may be considered synonymous with the more general terms "substrate" or "target portion," respectively. The substrates mentioned herein may be processed before or after exposure in, for example, a track unit (a tool typically used to apply a resist layer to the substrate and develop the exposed resist), a measurement unit, and / or an inspection unit. Where applicable, the disclosure herein may be applied to such and other substrate processing tools. Furthermore, the substrate may be processed more than once, for example to produce multilayer ICs, such that the term "substrate" as used herein may also refer to a substrate that includes multiple processed layers.

[0153] While the above description can be specifically referenced to the use of aspects in the context of optical lithography, it should be understood that aspects can be used in other applications (e.g., imprint lithography) and are not limited to optical lithography where circumstances permit. In imprint lithography, the morphology in a patterning apparatus defines a pattern generated on a substrate. The morphology of the patterning apparatus can be pressed into a resist layer supplied to the substrate, on which the resist is cured by applying electromagnetic radiation, heat, pressure, or a combination thereof. After the resist has cured, the patterning apparatus is removed from the resist, thereby leaving a pattern therein.

[0154] It should be understood that the wording or terminology used herein is for descriptive rather than limiting purposes, and that the terminology or terminology used herein should be interpreted by those skilled in the art in light of the teachings herein.

[0155] As used herein, the term "substrate" describes a material on which a layer of material has been added. In some respects, the substrate itself may be patterned, and the material added on top of the substrate may also be patterned, or may remain unpatterned.

[0156] The following examples are illustrative and not intended to limit any aspect of this disclosure. Other suitable modifications and adaptations to various conditions and parameters commonly encountered in the art and which will be understood by those skilled in the art are within the spirit and scope of this disclosure.

[0157] While specific reference may be made herein to the use of devices and / or systems in the manufacture of ICs, it should be clearly understood that such devices and / or systems have many other possible applications. For example, they can be used to manufacture integrated optical systems, guide and detection patterns for magnetic domain memories, LCD panels, thin-film magnetic heads, etc. Those skilled in the art will understand that in the context of such alternative applications, any use of the terms “mask,” “wafer,” or “die” herein should be regarded as being replaced by the more general terms “mask,” “substrate,” and “target portion,” respectively.

[0158] While specific aspects have been described above, it should be understood that these aspects may be practiced in other ways than those described. The description is not intended to limit the scope of the claims.

[0159] It should be understood that the Description of the Invention section, rather than the Summary of the Invention section, is intended to be used to interpret the claims. The Summary of the Invention section may set forth one or more, but not all, exemplary aspects contemplated by one or more inventors, and is therefore not intended to limit the aspects and the appended claims in any way.

[0160] The foregoing has described aspects by means of functional building blocks illustrating the implementation of specific functions and their relationships. For ease of description, the boundaries of these functional building blocks have been arbitrarily defined. Alternative boundaries can be defined as long as the specified functions and their relationships are properly performed.

[0161] The foregoing description of specific aspects will thus fully reveal the general nature of the aspects: without departing from the general conception of the aspects, others can easily modify and / or adapt these specific aspects for various applications by applying knowledge known to those skilled in the art, without excessive experimentation. Therefore, based on the teachings and instructions presented herein, such adaptations and modifications are intended to fall within the meaning and scope of equivalents of the disclosed aspects.

[0162] The breadth and scope of these aspects should not be limited by any of the exemplary aspects described above, but should be defined solely by the following claims and their equivalents.

Claims

1. A sensor device, comprising: A transient optical pattern, configured to induce a material change in an alignment mark, thereby forming an effective alignment mark; A probe beam configured to interact with the effective alignment mark; and A detector configured to measure diffracted or reflected light from the effective alignment mark generated by the probe beam.

2. The sensor device according to claim 1, wherein, The material change includes a change in the refractive index of the alignment mark.

3. The sensor device according to claim 1, wherein, The change in material is proportional to the intensity of the instantaneous optical pattern.

4. The sensor device according to claim 1, wherein, The instantaneous optical pattern includes an interference pattern.

5. The sensor device according to claim 1, wherein, The instantaneous optical pattern originates from multiple deflected beams.

6. The sensor device according to claim 1, wherein, The instantaneous optical pattern includes arbitrary image patterns, grating patterns, checkerboard patterns, finite patterns, or combinations thereof.

7. The sensor device according to claim 1, wherein, The probe beam is configured to interact with the effective alignment mark within the time range of the material change.

8. The sensor device according to claim 1, wherein, The diffracted light includes a first-order diffracted beam (I) from the effective alignment mark. -1 I +1 ).

9. The sensor device according to claim 1, wherein, The diffracted light is diffracted from the spatial periodic pattern of the effective alignment mark, which is formed by the combination of the instantaneous optical pattern and the alignment mark.

10. The sensor device according to claim 9, wherein, The spatial periodic pattern includes one or more spatial harmonics of the instantaneous optical pattern.

11. The sensor device according to claim 10, wherein, The relative periodicity between the period of the instantaneous optical pattern and the period of the alignment mark increases the resolution of the sensor device as the relative periodicity decreases.

12. The sensor device according to claim 11, wherein, The relative periodicity increases the resolution of the sensor device by at least 4 times.

13. The sensor device of claim 1, further comprising a processor coupled to the detector and configured to determine the position of the alignment mark based on the asymmetry of the diffracted light.

14. The sensor device according to claim 1, wherein: The alignment mark is adjustable relative to the instantaneous optical pattern and the probe beam. The instantaneous optical pattern can be adjusted relative to the alignment mark and the probe beam, or The probe beam can be adjusted relative to the alignment mark and the instantaneous optical pattern.

15. The sensor device of claim 1, further comprising an interferometric measuring device configured to receive the diffracted light and cause the diffracted light to interfere with itself to generate an alignment signal.

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