System and method for matching tools

Abstract

The present disclosure relates to systems and methods of matching tools. In one method of matching tools, a plurality of aberration maps of at least two optical systems of at least two exposure tool are determined. A first layout pattern is projected onto a substrate by using the optical system of each of the at least two exposure tools to produce a resist pattern. At least one Zernike coefficient of the at least two optical systems is adjusted based on the determined aberration maps of the at least two optical systems to minimize a critical dimension variation in a first region of the resist pattern on each respective substrate.

Description

Technical Field

[0001] This disclosure relates to systems and methods for matching exposure machine tools, and more particularly to systems and methods for adjusting the Zernike coefficients of exposure machine tools based on the aberration maps of the exposure machine tools to match the exposure machine tools. Background Technology

[0002] Multiple scanner tools are used on semiconductor device production lines. Therefore, it is crucial that each scanner tool on the production line producing the same pattern has, for example, the same critical dimension (CD). One method for producing the same CD when layout patterns are projected onto the substrate by different scanner tools on the same production line involves matching each scanner tool with a standard scanner tool that offers the best performance among scanner tools. The scanner tool matched to the standard scanner tool can then produce substantially the same CD for all layout patterns. Matching production line scanner tools to the standard scanner tool requires designing one scanner tool to be the standard scanner tool for the production line and maintaining that tool as the standard scanner tool, which is resource-intensive. Therefore, alternative, less expensive methods are needed to match production line scanner tools. Summary of the Invention

[0003] According to some embodiments of this disclosure, a method for matching tools includes: determining multiple aberration maps of at least two optical systems of at least two exposure tools; and adjusting at least one Zernike coefficient of the at least two optical systems based on the determined aberration maps of the at least two optical systems to minimize critical dimension (CD) variation between the at least two exposure tools. The method further includes projecting a first layout pattern onto a substrate using the optical systems of each of the at least two exposure tools to generate a photoresist pattern, and determining whether the critical dimension variation in a first region of the photoresist pattern on each of the substrates is within a threshold. The method further includes repeating the adjustment, generation, and determination operations if the critical dimension variation in the first region is not within the threshold.

[0004] According to some embodiments of this disclosure, a method for matching tools includes: determining multiple aberration maps of at least two optical systems of at least two exposure tools; and adjusting at least two Zernike coefficients of the at least two optical systems based on the determined aberration maps of the at least two optical systems to minimize critical dimension (CD) variation between the at least two exposure tools. The method further includes projecting a first layout pattern onto a substrate using the optical systems of each of the at least two exposure tools to generate a first photoresist pattern, and projecting a second layout pattern onto the substrate using the optical systems of each of the at least two exposure tools to generate a second photoresist pattern. The method further includes determining whether critical dimension variations in a first region of the first photoresist pattern and in a second region of the second photoresist pattern on the respective substrates are within thresholds. The method further includes repeating the adjustment operation, the generation of the first photoresist pattern, the generation of the second photoresist pattern, and the determination operation if the critical dimension variations in the first and second regions are not within thresholds.

[0005] According to some embodiments of this disclosure, a system for matching tools includes at least two exposure machine tools, each of the exposure machine tools including an optical system, and each of the optical systems including at least two mirrors. The optical system further includes a controller, an image detector, an analyzer module, and a actuator coupled to the at least two mirrors. In each optical system, the analyzer module is configured to receive an aberration map of the respective optical system from the image detector and to transmit the aberration map of the respective optical system to the controller. In each optical system, the controller is configured to receive aberration maps of the other optical systems. The controller is also configured to adjust at least one Zernike coefficient of the respective optical system, and to adjust at least one Zernike coefficient of the other optical system based on the aberration maps of the respective optical system and the aberration maps of the other optical systems, to minimize critical dimension (CD) variation when at least two exposure machine tools are used in a photo lithography process that projects a layout pattern onto a substrate using an extreme ultraviolet (EUV) radiation beam. Attached Figure Description

[0006] This disclosure is best understood by reading the following embodiments in conjunction with the accompanying drawings. It should be noted that, according to industry standard practice, the multiple features are not drawn to scale. In fact, for clarity of discussion, the dimensions of the multiple features can be arbitrarily increased or decreased.

[0007] Figure 1A schematic diagram of an EUV lithography system showing an EUV radiation source with laser-produced plasma (LPP) and an exposure device.

[0008] Figure 2 This diagram shows an EUV lithography system with an LPP EUV radiation source, an exposure device, and a reticle mount structure.

[0009] Figure 3A , Figure 3B , Figure 3C , Figure 3D Display of the exposure device and parts thereof.

[0010] Figure 4A , Figure 4B This disclosure shows a plurality of dies on a substrate according to some embodiments of the present disclosure, and a plurality of slits of a die on the substrate, the layout pattern of which is projected onto the die by a mirror.

[0011] Figure 5A , Figure 5B , Figure 5C , Figure 5D This disclosure shows at least one mirror and a controller for the mirror, representing some embodiments of the present disclosure.

[0012] Figure 6A , Figure 6B The present disclosure shows a mirror and a mirror actuator according to some embodiments.

[0013] Figure 7A , Figure 7B A system that displays multiple exposure machine tools according to some embodiments of the present disclosure, and a system for matching multiple exposure machine tools.

[0014] Figure 8A , Figure 8B This disclosure shows key dimensional variations of different exposure machine tools in a system with multiple exposure machine tools, before and after exposure machine tool matching, according to some embodiments of the present disclosure.

[0015] Figure 9 This disclosure shows flowcharts illustrating processes for matching multiple exposure machine tools according to some embodiments of the present disclosure.

[0016] Figure 10A , Figure 10B This illustration shows an instrument, according to some embodiments of the present disclosure, for matching multiple exposure machine tools.

[0017] Figure 11A , Figure 11B, Figure 11C , Figure 11D This disclosure illustrates the sequential manufacturing operations of a method for manufacturing a semiconductor device according to some embodiments of the present disclosure.

[0018] The reference numerals in the attached figures are explained as follows:

[0019] 29, 31: Extreme ultraviolet radiation beams (EUV radiation beams)

[0020] 85: Droplet trap

[0021] 100: Extreme ultraviolet radiation source (EUV radiation source)

[0022] 105: Chamber

[0023] 110: Concentrator

[0024] 111: Focusing Unit

[0025] 115: Droplet Generator

[0026] 117: Nozzle

[0027] 143: Pattern

[0028] 200: Exposure device

[0029] 201: Schematic diagram

[0030] 202: Illumination Optical Components

[0031] 204: Projection Optical Elements

[0032] 205: Marking plate

[0033] 208, 218: Aperture

[0034] 210: Wafer / Substrate

[0035] 222, 224, 226, 228, 232, 234, 236, 238, 242, 244, 321, 400, 430, M1, M2, M3, M4, M5, M6: Mirrors

[0036] 225: Marking Patch Installation Structure

[0037] 230: Analyzer Module

[0038] 235: Image Detector

[0039] 300, 350: Optical System

[0040] 301: Excitation laser source

[0041] 302: Lighting source

[0042] 304: Lens

[0043] 306: Objective lens system

[0044] 308: Distance

[0045] 310: Radiation beam

[0046] 311: Reflected radiation beam

[0047] 312: Converging Beam

[0048] 313: Laser Generator

[0049] 314: Blade

[0050] 320: Laser-guided optical components

[0051] 330: Focusing instrument

[0052] 331: Exit pupil

[0053] 332: Side view

[0054] 333: Entrance pupil

[0055] 335: Direction

[0056] 338, 342: Lines

[0057] 343: Reflective grating pattern

[0058] 351: Brake

[0059] 352: Zenik Plate

[0060] 354, 476: Length

[0061] 460: Controller

[0062] 470: Grain

[0063] 472: Narrow Slit

[0064] 474: Width

[0065] 490: Wafer

[0066] 505, 510: Diameter

[0067] 570: Mirror Control System

[0068] 700: Computer System

[0069] 701: Computer

[0070] 702: Keyboard

[0071] 703: Mouse

[0072] 704: Monitor

[0073] 705: Optical Disc Read-Only Memory Drive

[0074] 706: Disk drive

[0075] 710: Main Controller

[0076] 711: Microprocessor Unit (MPU)

[0077] 712: Read-Only Memory (ROM)

[0078] 713: Random Access Memory (RAM)

[0079] 714: Hard Drive

[0080] 715: Bus

[0081] 721: CD

[0082] 722: Disk

[0083] 750, 900: Process

[0084] AA, BB: points

[0085] BF: Base Flooring

[0086] DMP1, DMP2: Dampers

[0087] DP: Target droplet

[0088] EUV: Extreme Ultraviolet Radiation

[0089] L1, L2: Lenses

[0090] LR0: Laser beam

[0091] LR2: Excitation laser beam

[0092] MF: Main Floor

[0093] PP1, PP2: Base plates

[0094] PR: Photoresist layer

[0095] S752, S754, S756, S758, S760, S762, S902, S904, S906, S908, S910: Operation

[0096] TL: Target Layer

[0097] T1, T2, T3, T4: Exposure machine tools

[0098] ZE: Excitation Region Detailed Implementation

[0099] The following provides several different embodiments or examples to achieve different features of the provided object. Furthermore, specific examples of elements and arrangements are described below to simplify the embodiments of this disclosure. These examples are, of course, merely examples and should not be considered limiting. For example, the formation of the first feature above the second feature in the following embodiments may include embodiments where the first and second features are in direct contact, or embodiments where additional features are formed between the first and second features, in which case the first and second features do not directly contact each other. Furthermore, reference numerals and / or letters are repeated in various examples of the embodiments of this disclosure. Such repetition is for brevity and clarity and is not intended to determine the relationship between the various embodiments and / or configurations.

[0100] Furthermore, spatial relative terms, such as "below," "below," "lower," "above," and "higher," are used herein for convenience in describing the relationship between one element or feature and another. Spatial relative terms are intended to include different orientations of the device in use or operation other than those depicted in the figures. The device may face other orientations (rotated 90 degrees or in other orientations), and the descriptive terms of spatial relative relationships used herein may be interpreted accordingly. Additionally, the term "composes" may mean "includes" or "components of." In this disclosure, "one of A, B, and C" unless otherwise stated represents "A, B, and / or C" (A, B, C, A and B, A and C, B and C, or A, B, and C), and does not represent one element in A, one element in B, and one element in C.

[0101] In some embodiments, to avoid matching the exposure tools on the production line with standard exposure tools, the exposure tools are matched to each other such that the CD variation of the same pattern produced on all exposure tools on the production line is within a threshold. To match the exposure tools, at least one Zernike coefficient is adjusted in the optimization process to adjust (e.g., improve) the aberration map of the exposure tool. In practice, changing the Zernike coefficient is achieved by adjusting the position and / or curvature of the mirrors or lenses in the exposure device used for the exposure tool.

[0102] Figure 1This diagram shows an EUV lithography system with a laser-produced plasma (LPP) type extreme ultraviolet (EUV) radiation source and an exposure device. The EUV lithography system includes an EUV radiation source 100 (EUV light source), an exposure device 200, and an excitation laser source 301. The EUV radiation source 100 generates EUV radiation, and the exposure device 200 is, for example, an exposure machine tool. Figure 1 As shown, in some embodiments, the EUV radiation source 100 and the exposure device 200 are mounted on the main floor MF of the clean room, while the excitation laser source 301 is mounted in the base floor BF located below the main floor MF. Each of the EUV radiation source 100 and the exposure device 200 is placed on pedestal plates PP1 and PP2 respectively via dampers DMP1 and DMP2. The EUV radiation source 100 and the exposure device 200 are coupled to each other by a coupling mechanism, which includes a focusing unit 111. In some embodiments, the lithography system includes the EUV radiation source 100 and the exposure device 200.

[0103] The lithography system is an EUV lithography system designed to expose a resist layer using EUV light (which can also be interchangeably referred to herein as EUV radiation). The resist layer is a material sensitive to EUV light. The EUV lithography system employs an EUV radiation source 100 to generate EUV light, for example, EUV light with wavelengths between approximately 1 nanometer (nm) and approximately 50 nanometers. In a particular example, the EUV radiation source 100 generates EUV light with a wavelength centered at approximately 13.5 nanometers. In this embodiment, the EUV radiation source 100 uses a laser-generated plasma (LPP) mechanism to generate EUV radiation.

[0104] Exposure apparatus 200 includes multiple reflective optical components (e.g., convex / concave / flat mirrors), a mask holding mechanism including a mask stage, and a wafer holding mechanism (e.g., a substrate holding mechanism or a wafer stage). EUV radiation generated by EUV radiation source 100 is guided by the reflective optical components to the mask fixed on the mask stage. In some embodiments, the mask stage includes an electrostatic chuck (e-chuck) to hold the mask. Because gas molecules absorb EUV light, the lithography system used for EUV lithography patterning is maintained in a vacuum or low-pressure environment to avoid EUV intensity loss. As previously described, exposure apparatus 200 is maintained in a vacuum environment and reticles are mounted on a substrate on which a photoresist layer is deposited. EUV radiation generated by EUV radiation source 100 is guided by optical elements to project a mask onto the photoresist layer of the substrate. In some embodiments, exposure apparatus 200 is an exposure machine tool. The optical elements (e.g., exposure machine tools) of exposure apparatus 200 are referenced. Figure 2 A more detailed description is available.

[0105] In this specification, the terms "mask," "photomask," and "reticle" are used interchangeably. Similarly, the terms "resist" and "photoresist" are used interchangeably. In some embodiments, the mask is a reflective mask. In some embodiments, the mask comprises a substrate made of a suitable material, such as a low thermal expansion material or fused quartz. In several examples, the material comprises TiO2-doped SiO2, or other suitable materials with low thermal expansion. The mask comprises multiple reflective layers (MLs) deposited on the substrate. The reflective layers comprise multiple film pairs, such as molybdenum-silicon (Mo / Si) film pairs (e.g., in each film pair, a molybdenum layer is on top of or under a silicon layer). Alternatively, the reflective layers may comprise molybdenum-beryllium (Mo / Be) film pairs, or other suitable materials configured to highly reflect EUV light. The mask may further include a capping layer, such as ruthenium (Ru), disposed on the reflective layer for protection. The mask may also include an absorption layer, such as a tantalum boron nitride (TaBN) layer, deposited on the reflective layer. The absorption layer is patterned to define an integrated circuit (IC).

[0106] Exposure apparatus 200 includes a projection optics module for imaging a pattern of a mask onto a semiconductor substrate fixed on a substrate stage of the exposure apparatus 200, and the semiconductor substrate having a resist coating. The projection optics module typically includes a reflective optic. EUV radiation (EUV light) guided from the mask, carrying the pattern defined on the mask, is collected and guided by the projection optics module (e.g., a mirror) to form an image on the resist.

[0107] In several embodiments of this disclosure, the semiconductor substrate is a semiconductor wafer, such as a patterned silicon wafer or other type of wafer. In embodiments of this disclosure, the semiconductor substrate is coated with an EUV-sensitive resist layer. Multiple components, including those described above, are integrated together and operable to perform multiple lithography exposing processes. The lithography system may further include or be integrated with (or coupled to) other modules.

[0108] like Figure 1 As shown, the EUV radiation source 100 includes a droplet generator 115 and a laser-generated plasma (LPP) collector mirror 110 encapsulated in a chamber 105. The droplet generator 115 generates a plurality of target droplets DP, which are then supplied to the chamber 105 via nozzles 117. In some embodiments, the target droplets DP are tin (Sn), lithium (Li), or an alloy of tin and lithium. In some embodiments, the radius of each target droplet DP ranges from approximately 10 micrometers (μm) to approximately 100 micrometers. For example, in one embodiment, the target droplets DP are tin droplets, each with a radius of approximately 10 μm, approximately 25 μm, approximately 50 μm, or any other radius between these values. In some embodiments, the target droplet DP is supplied by nozzle 117 at a rate of approximately 50 droplets per second (i.e., an ejection frequency of approximately 50 Hz) to approximately 50,000 droplets per second (i.e., an ejection frequency of approximately 50 kHz). For example, in one embodiment, the target droplet DP is supplied by nozzle 117 at an ejection frequency of approximately 50 Hz, approximately 100 Hz, approximately 1 kHz, approximately 10 kHz, approximately 25 kHz, approximately 50 kHz, or any ejection frequency between these frequencies. The target droplet DP is ejected via nozzle 117 into the zone of excitation ZE (e.g., the target droplet location) at a speed of approximately 10 m / s to approximately 100 m / s. For example, in one embodiment, the velocity of the target droplet DP is approximately 10 m / s, approximately 25 m / s, approximately 50 m / s, approximately 75 m / s, approximately 100 m / s, or any velocity between these velocities.

[0109] The excitation laser beam LR2 generated by the excitation laser source 301 is a pulsed beam. The laser pulses of the excitation laser beam LR2 are generated by the excitation laser source 301. The excitation laser source 301 may include a laser generator 313, a laser guide optic 320, and a focusing apparatus 330. In some embodiments, the laser generator 313 includes a carbon dioxide (CO2) or neodymium-doped yttrium aluminum garnet (Nd:YAG) laser source with wavelengths in the infrared region of the electromagnetic spectrum. For example, in one embodiment, the wavelength of the excitation laser source 301 is 9.4 μm or 10.6 μm. The laser beam LR0 generated by the excitation laser source 301 is guided by the laser guiding optics 320 and focused by the focusing instrument 330 onto the excitation laser beam LR2 introduced into the EUV radiation source 100. In some embodiments, in addition to CO2 and Nd:YAG lasers, the excitation laser beam LR2 is generated by a gas laser including an excimer gas discharge laser, a helium-neon laser, a nitrogen laser, a transversely excited atmospheric (TEA) laser, an argon ion laser, a copper vapor laser, a krypton fluoride (KrF) laser, or an argon fluoride (ArF) laser; or by a solid-state laser including a Nd:glass laser, a ytterbium-doped glass laser, a ceramic laser, or a ruby ​​laser. In some embodiments, the excitation laser source 301 also generates a non-ionizing laser beam LR1 (not shown), and the non-ionizing laser beam LR1 is also focused by the focusing instrument 330 to preheat a given target droplet by generating a preheating laser pulse.

[0110] In some embodiments, the excitation laser beam LR2 comprises a preheating laser pulse and a main laser pulse. In such embodiments, the preheating laser pulse (which may also be interchangeably referred to herein as a pre-pulse) is used to heat (or preheat) a given target droplet to create a low-density target plume with multiple smaller droplets, which is then heated (or reheated) by the main laser pulse from the main laser to produce more EUV light emission compared to when no preheating laser pulse is used.

[0111] In several embodiments, the preheating laser pulse has a spot size of approximately 100 μm or less, and the main laser pulse has a spot size between approximately 150 μm and approximately 300 μm. In some embodiments, the pulse duration of both the preheating and main laser pulses is between approximately 10 nanoseconds (ns) and approximately 50 nanoseconds, and the pulse frequency is between approximately 1 kHz and approximately 100 kHz. In several embodiments, the average power of both the preheating and main lasers is between approximately 1 kilowatt (kW) and approximately 50 kilowatts. In one embodiment, the pulse frequency of the excitation laser beam LR2 is matched to the ejection frequency of the target droplet DP.

[0112] The excitation laser beam LR2 is guided into the excitation region ZE via a window (or lens). The window is made of a suitable material and is substantially transparent to the laser. The generation of the laser pulse is synchronized with the ejection of the target droplet DP through nozzle 117. As the target droplet moves through the excitation region, a pre-pulse heats the target droplet and transforms it into a low-density target conduit. The delay between the pre-pulse and the main pulse is controlled to allow the formation of the target conduit and to extend the target conduit to a preferred size and geometry. In several embodiments, the pre-pulse and the main pulse have the same pulse duration and peak power. When the main pulse heats the target conduit, a high-temperature plasma is generated. The plasma emits an extreme ultraviolet (EUV) radiation beam 29, which is collected by a focusing mirror 110. The focusing mirror 110 and the EUV focusing mirror further reflect and focus the EUV radiation beam 29 for the lithography process performed by the exposure apparatus 200. Target droplets (DP) that do not interact with the laser pulse are collected by droplet catcher 85. For example... Figure 1As shown, the EUV radiation beam 29 from the condenser lens 110 is focused into the focusing unit 111 between the EUV radiation source 100 and the exposure apparatus 200. The EUV radiation beam 29 entering the exposure apparatus 200 from the focusing unit 111 is consistent with the EUV radiation originating from the focused point (e.g., a point source) in the focusing unit 111.

[0113] One method for synchronizing the generation of pulses (one or both of a pre-pulse and a main pulse) from an excitation laser with the arrival time of a target droplet at the excitation region involves detecting a passing target droplet at a given location and using the passing target droplet as a signal to trigger the excitation pulse (or pre-pulse). In this method, it is assumed, for example, that the transit time of the target droplet is t. o This indicates that the time of EUV radiation generation (and detection) is expressed in t. rad- It indicates that the distance between the detected position of the target droplet and the center of the excitation region is d, and the velocity of the target droplet is v. dp The calculation can be performed as follows:

[0114] v dp =d / (t) rad -t o )

[0115] Because the droplet generator 115 is expected to repeatedly supply droplets at a fixed rate, once the rate v... dp The calculation is complete after the target droplet is detected passing through the given position, with a time delay d / v. dp An excitation pulse is triggered to ensure that the excitation pulse and the target droplet arrive at the center of the excitation region simultaneously. In some embodiments, the main pulse is triggered after a fixed delay following the pre-pulse. In one embodiment, the target droplet velocity value v is set if necessary. dp By periodically measuring t rad The calculation is periodically recalculated, and the generation of pulses is resynchronized with the arrival time of the target droplet.

[0116] Figure 2 This is a schematic diagram of an EUV lithography system with an LPP EUV radiation source, an exposure device, and a reticle mount structure. Figure 2 Schematic diagram 201 shows an EUV lithography system having an LPP EUV radiation source 100, an exposure apparatus 200, and a puncture plate mounting structure 225 for displaying puncture plates 205 (e.g., photomasks). See above reference. Figure 1As described, the EUV radiation source 100 generates an EUV radiation beam 29. After exiting the EUV radiation source 100 through an aperture 208, the EUV radiation beam 29 passes through a focusing unit 111 outside the EUV radiation source 100. In some embodiments, the aperture 208 is made of a material transparent to EUV radiation.

[0117] Figure 2 The EUV lithography system also includes an exposure device 200. The exposure device 200 includes multiple convex, concave, or plane mirrors. As shown, in some embodiments, the EUV radiation beam 29 is focused by a focusing unit 111 between the EUV radiation source 100 and the exposure device 200, and then enters the exposure device 200 through an aperture 218 made of a material transparent to EUV radiation. After entering the exposure device 200, the EUV radiation beam 29 is guided to a datum plate 205 by an illumination optic 202. As shown, the EUV radiation beam 29 is guided and reflected by mirror 222 (e.g., a converging mirror) of the illumination optics 202, guided to mirror 224 (e.g., another converging mirror) of the illumination optics 202 and reflected therefrom, guided to mirror 226 (e.g., a diverging mirror) of the illumination optics 202 and reflected therefrom, guided to mirror 228 (e.g., a plane mirror) of the illumination optics 202 and reflected therefrom, to impinge onto the marking plate 205 (e.g., a reflective photomask). Extreme ultraviolet (EUV) radiation beam 31 is reflected from the layout pattern of the marking plate 205.

[0118] like Figure 2As shown, after being reflected from the layout pattern of the caliper 205, the EUV radiation beam 31 is guided by the projection optics 204 to the wafer 210 (a substrate with a photoresist layer), or optionally to the image detector 235. As shown in the figure, the EUV radiation beam 31 is guided to and reflected from mirror 232 (M1) (e.g., a plane mirror) of the projection optics 204, guided to and reflected from mirror 234 (M2) (e.g., a diffuser), guided to and reflected from mirror 234, guided to and reflected from mirror 236 (M3) (e.g., another diffuser), guided to and reflected from mirror 238 (M4) (e.g., a converging mirror), guided to and reflected from mirror 242 (M5) (e.g., another converging mirror), and guided to and reflected from mirror 244 (M6) (e.g., another converging mirror) to strike the wafer 210 or image detector 235. In some embodiments, as referenced below... Figure 5A , Figure 5B ,or Figure 5C As described, at least one mirror 232, 234, 236, 238, or 242 is controllable; for example, the position and / or curvature of the mirror can be adjusted to change the wavefront reflected from these mirrors. Furthermore, as shown, an image detector 235 is connected to an analyzer module 230, which receives images captured by the image detector 235. In some embodiments, as described below, the analyzer module 230 performs analysis of the captured images and detects interference fringe patterns. In some embodiments, the projection optics 204 and / or illumination optics 202 are referred to as the optical system of the exposure apparatus 200 (e.g., an exposure machine tool). In some embodiments, an EUV radiation source 100 is included in the optical system. In some embodiments, the image detector 235 is included in the optical system.

[0119] Figure 3A , Figure 3B , Figure 3C , Figure 3D Display of the exposure device and parts thereof. Figure 3A Display exposure device 200, and display by Figure 2An illumination optics element 202 guides the EUV radiation beam 29 to a reflective grating pattern 343. As shown, the exposure apparatus 200 (e.g., an exposure machine tool) has a reflective grating pattern 343 instead of a grating plate 205. The EUV radiation beam 29 strikes the reflective grating pattern 343 and is imaged onto an image detector 235 by a projection optics element 204. The image captured by the image detector 235 is analyzed by an analyzer module 230. In some embodiments, the image captured by the image detector 235 displays the aberrations of the projection optics element 204. Therefore, based on the resolution and orientation of the reflective grating pattern 343, the analyzer module 230 determines the Zernike expansion coefficients of the aberrations of the projection optics element 204, for example, the coefficients when the aberrations are projected onto the space of Zernike polynomials. In some embodiments, gratings with different resolutions and orientations are used as the reflective grating pattern 343, thus allowing the determination of multiple Zernike expansion coefficients of the aberration map of the projection optical element 204. Therefore, in some embodiments, by using multiple reflective gratings with multiple resolutions and multiple orientations, the aberrations of the projection optical element 204 can be approximated using the determined Zernike expansion coefficients.

[0120] Figure 3BAn optical system 300 is shown in some embodiments as used in a transmissive lithographic system. The optical system 300 displays an illumination source 302 at a distance 308 from a lens 304. The lens 304 transmits a radiated beam of light from the light source through a pattern 143. The transmitted radiated beam 310 is converged using an objective lens system 306 to produce a convergent beam 312, creating a projected lithographic pattern of pattern 143 on a substrate 210 or an image detector 235. In some embodiments, the illumination source 302 generates deep ultraviolet (DUV) radiation in the range of 100 nm to 290 nm, therefore the radiated beam 310 is a DUV radiated beam. As shown, a blade 314 blocks any radiation outside the exit pupil 331 of the optical system 300. In some embodiments, pattern 143 is consistent with the layout pattern of tracing sheet 205, and thus the layout pattern of tracing sheet 205 is projected onto a photoresist-coated substrate 210, and a photoresist pattern is generated on substrate 210 after development. In some embodiments, pattern 143 is a grating used to determine the Zernike expansion coefficient of the aberration map of the exposure machine tool. Therefore, pattern 143 can be replaced by multiple other gratings with multiple other resolutions and multiple other orientations to determine other Zernike expansion coefficients of the aberration map of the exposure machine tool (e.g., the optical system 300 of the exposure machine tool) based on an image captured by image detector 235 and subsequently analyzed by analyzer module 230.

[0121] Figure 3C An optical system 350 is shown in some embodiments for use in a lithography system. The optical system 350 displays an illumination source 302. A lens 304 transmits a radiated beam from the illumination source 302. The radiated beam is reflected by a mirror 321 and directed toward a reflective grating pattern 343, producing a reflected radiated beam 311 reflected from the reflective grating pattern 343. The reflected radiated beam 311 is converged using an objective lens system 306 to produce a converged beam 312 and create a projected pattern of the reflective grating pattern 343 on a substrate 210 or an image detector 235. Figure 3CThe exit pupil 331 of the optical system 350 is also shown. In some embodiments, the illumination source 302 (e.g., a light source or an input source) is a deep ultraviolet (DUV) light source with a wavelength between approximately 100 nm and approximately 290 nm, or an extreme ultraviolet (EUV) light source with a wavelength between approximately 10 nm and approximately 100 nm. In some embodiments, the reflective grating pattern 343 is a reflective grating, and different gratings with multiple resolutions and multiple directions are used to determine the Zernike expansion coefficients of the aberrations of the optical system 350 based on the image captured by the image detector 235 and subsequently analyzed by the analyzer module 230.

[0122] Figure 3D The image shows an objective lens system 306 having an entrance pupil 333 and an exit pupil 331. The objective lens system 306 may include at least two lenses L1 and L2 for guiding a reflected radiation beam 311 or a transmitted radiation beam 310 onto a substrate 210 (e.g., a wafer) or an image detector 235. In some embodiments, the objective lens system 306 includes at least one Zernike plate 352, which is movable along a length 354 within the objective lens system 306 to be positioned before, between, or after the objective lens. In some embodiments, at least two Zernike plates 352 are used to compensate for (e.g., correct) aberrations in the optical system 350 or to correct aberrations in the optical system 300.

[0123] Figure 4A , Figure 4B This disclosure shows a plurality of dies on a wafer and a plurality of slits on the dies, the layout pattern of which is projected onto the dies by a mirror. Figure 4A The display shows a wafer 490 containing at least two dies 470, for example, a wafer 490 with... Figure 2 The same substrate as substrate 210. As described below, mirror 400 is used as part of a plurality of mirrors of illumination optics 202 and / or as part of a plurality of mirrors of projection optics 204 to project the layout pattern of tracing sheet 205 onto at least one die 470 of wafer 490. Figure 4B The wafer 490 is shown as a die 470. As shown, the die 470 has a length 476 and a width 474. In some embodiments, the length 476 or the width 474 of the die 470 is between approximately 4 millimeters (mm) and approximately 30 millimeters. In some embodiments, the width 474 of the die 470 is divided into at least two slits 472, or between 10 and 20 slits 472. In some embodiments, the aberrations of the optical system 300 or the optical system 350 are determined separately in each slit 472 of the die 470, and the Zernike coefficient (e.g., Zernike expansion coefficient) of the slit 472 is determined.

[0124] Figure 5A , Figure 5B , Figure 5C , Figure 5D This disclosure shows at least one mirror and a controller for the mirror, representing some embodiments. Figure 5A , Figure 5B , Figure 5C As shown, mirror 430 or 400 is part of illumination optics 202 or projection optics 204. In some embodiments, such as Figure 5A As shown in the mirror control system 570, mirror 430 is coupled to actuator 351, which includes, for example, at least one motor or piezoelectric electronic device to move mirror 430 along the X, Y, and / or Z directions by means of controller 460. In some embodiments, the Y direction is perpendicular to the surface of the mirror (parallel to the optical axis). In some embodiments, controller 460 is coupled to actuator 351 to control the downward and upward movement of mirror 430 or mirror 400 in the Z direction, the lateral movement in the X direction, and the backward and forward movement in the Y direction. In some embodiments, mirror 430 or mirror 400 moves within ± approximately 20 mm along the X, Y, or Z directions. In some embodiments, the tilt angle of mirror 430 or mirror 400 is also controlled to change the direction of the wavefront reflected from mirror 430 or mirror 400 and to change the phase of the wavefront reflected from mirror 430 or mirror 400. Therefore, in some embodiments, the controller 460 adjusts the direction and phase of the EUV radiation beam 29 or EUV radiation beam 31 away from the illumination optics 202 or projection optics 204 by moving and / or tilting the mirror 430 or mirror 400.

[0125] like Figure 5A , Figure 5B ,or Figure 5C As shown, the controller 460 applies force via a brake to at least two positions, at both ends of the diameter, and the perimeter of each mirror 430 or 400 to adjust (e.g., increase or decrease) the curvature of the mirror 430 or 400, for example, perpendicular to the Y direction. As described above, the mirrors can be incorporated into mirrors 222, 224, 226, or 228 of the illumination optics 202, or into mirrors 232, 234, 236, 238, or 242 of the projection optics 204. Therefore, controlling the curvature and / or position of the aforementioned mirrors 430 or 400 can adjust at least two Zernike coefficients and can reduce aberrations in the projection optics 204 or the illumination optics 202. Figure 5A , Figure 5BAs shown, pressure is applied to both ends of the diameter, at least along the Z-direction or the X-direction. Figure 5C As shown, pressure is applied to at least both ends of diameters 505 and 510, with diameters 505 and 510 having angles of 45 degrees and 135 degrees with the X direction, respectively.

[0126] Figure 5C The mirror 400 is coupled to the controller 460 via the actuator 351, and the controller 460 adjusts the direction and / or phase of the wavefront reflected from the mirror 400. Therefore, if the mirror 400 is used as one of a plurality of mirrors for the illumination optics 202 and / or the projection optics 204, the Zernike coefficients corresponding to the aberrations of the illumination optics 202 and / or the projection optics 204 can be adjusted.

[0127] Figure 5D The display includes an exposure device 200 comprising mirrors M1, M2, M3, M4, M5, and M6, and mirrors M1, M2, M3, M4, M5, and M6 with... Figure 2 The mirrors 232, 234, 236, 238, 242, and 244 of the projection optics 204 are identical. At least one of mirrors M1, M2, M3, M4, or M5 is mirror 430 or 400 coupled to the controller 460 via actuator 351. As described above, the analyzer module 230 receives the aberration map of the projection optics 204 from the image detector 235. The controller 460 determines how to adjust the Zernike coefficients corresponding to the aberration map of the projection optics 204. The controller 460 then commands the actuator 351 to adjust at least one of mirrors M1, M2, M3, M4, or M5 to adjust the Zernike coefficients corresponding to the aberration map of the projection optics 204 to improve the critical dimension (CD) uniformity of the pattern generated by projecting the layout pattern of the tracing patch 205 onto the substrate 210. The controller 460 adjusts the curvature and / or position of at least one of mirrors M1, M2, M3, M4, or M5.

[0128] Figure 6A , Figure 6B The present disclosure shows a mirror and a mirror brake according to some embodiments. Figure 6A Display adjustment Figure 5A The position of mirror 430 is adjusted to adjust the beam projected onto the projection optics 204 on wafer 490 and to reduce aberrations on the die 470 and slit 472. For example... Figure 6AAs shown, by moving mirror 430 along the Y direction (the direction of light propagation of EUV radiation beam 29 or 31), the phase of the wavefront of the reflected EUV radiation beam 31 can be adjusted to reduce aberrations on the grain 470 and slit 472. As shown, actuator 351 moves at least one mirror 430 in direction 335 (the Y direction from point AA to point BB, i.e., in the direction of propagation of EUV radiation beam 31) or in the lateral direction 332, X direction, and / or Z direction.

[0129] In some embodiments, such as Figure 6B As shown, brake 351 is configured to apply pressure along line 338 to change the curvature of mirror 430 by altering the curvature perpendicular to line 342, for example, increasing or decreasing the curvature perpendicular to line 342 to change the focal position / distance of mirror 430. This also adjusts the phase of the wavefront of the reflected EUV radiation beam 31 to reduce aberrations on grain 470 and slit 472. In some embodiments, brake 351 includes a plurality of pistons or piezoelectric elements to change the curvature of mirror 430. In some embodiments, pressure is applied at at least two locations on the circumference of mirror 430 or 400, and the curvature changes perpendicular to line 342, adjusting the focal distance of mirror 430. In some embodiments, an increase in curvature results in a decrease in focal distance, while a decrease in curvature results in an increase in focal distance. In some embodiments, at least one mirror M1, M2, M3, M4, or M5, identical to mirror 430, is tilted relative to the direction of the reflected EUV radiation beam 31 to adjust the Zernike coefficient and reduce aberrations on the grain 470 and slit 472. In some embodiments, deformation and / or curvature changes are generated on the mirror by applying pressure to at least two points along the circumference of the mirror, or by applying pressure to at least two points on the back surface of the mirror, to generate a phase change in the wavefront reflected from the mirror to compensate for aberrations.

[0130] In some embodiments, the controller 460 simultaneously applies pressure to at least two mirrors M1, M2, M3, M4, or M5, or applies pressure to one of the mirrors M1, M2, M3, M4, or M5 individually to change the curvature of that mirror. In some embodiments, the change in curvature is within approximately ±5% of the original curvature (the focal length changes by ±5% of the original focal length). In some embodiments, the curvature and / or position of lenses L1 and L2 are controllable. Therefore, the curvature and / or position of lenses L1 and L2 produce... Figure 3D The effect of at least two Zernike plates 352 can, for example, adjust the Zernike coefficient corresponding to the aberration of the objective lens system 306.

[0131] In some embodiments, as described above, mirrors M1, M2, M3, M4, or M5 are one of a plane mirror, a convex mirror, or a concave mirror. Thus, by applying pressure to at least two points on the circumference of the aforementioned mirror, a plane mirror can become a convex mirror or a concave mirror; a convex mirror can be more convex or less convex, and a concave mirror can be more concave or less concave.

[0132] Figure 7A , Figure 7B A system that displays multiple exposure machine tools according to some embodiments of the present disclosure, and a system for matching multiple exposure machine tools. Figure 7A A computer system 700 displays multiple exposure tools, which are coupled to and communicate with each other. As shown, in some embodiments, all exposure tools are connected to a main controller 710, which controls at least four exposure tools, including exposure tools T1, T2, T3, and T4, each with a separate controller 460. In some embodiments, the main controller 710 commands the exposure tools T1, T2, T3, and T4 to determine the aberration map of the exposure tool, such as the aberration map of the optical system of the exposure apparatus 200, which includes illumination optics 202 and projection optics 204. Furthermore, the main controller 710 commands exposure machine tools T1, T2, T3, and T4 to change the Zernike coefficients of each exposure machine tool T1, T2, T3, and T4 based on the aberration maps of the exposure machine tools (e.g., the aberration map of one exposure machine tool and multiple aberration maps of other exposure machine tools) to reduce CD variation among the exposure machine tools T1, T2, T3, and T4. In some embodiments, there is no main controller 710, and the controller 460 of one of the exposure machine tools T1, T2, T3, and T4 performs the functions of the main controller 710. In some embodiments, the computer system 700 includes 5 to 10 exposure machine tools.

[0133] Figure 7BThe system is displayed to match the different exposure machine tools described above. The system displays process 750 for matching different exposure machine tools T1, T2, T3, T4, etc. Process 750 begins with operation S752, in which a sensitivity table for the Zernike polynomials of each exposure machine tool is determined (e.g., measured). In some embodiments, for all Zernike coefficients / polynomials, the effect of changes in Zernike coefficients on changes in the CD value of each exposure machine tool is determined, and the ratio between the change in CD value and the change in Zernike coefficients is determined as the sensitivity table for the Zernike polynomials of each exposure machine tool. In some embodiments, aberration maps are determined (e.g., measured) in each slit 472 of the wafer grains, thus determining (e.g., measuring) the sensitivity table for the Zernike polynomials of each exposure machine tool in each slit of the wafer grains. The same sensitivity ratio is then calculated using analog measurements.

[0134] In operation S754, it is determined whether the measured sensitivity value is consistent with the calculated value. For example, this is done so that when the Zernike coefficient increases, the change in the CD value also increases in both the measurement and calculation. When the measured sensitivity value is consistent with the calculated value, the Zernike coefficient is retained (e.g., used) during optimization. However, in operation S756, if the change in the Zernike coefficient is inconsistent with the change in CD in both the measurement and calculation, the corresponding Zernike coefficient and Zernike polynomial are ignored and not used in optimization. In some embodiments, the corresponding Zernike coefficient is set to 0. The Zernike coefficient whose change in Zernike coefficient is consistent with the change in CD in both the measurement and calculation is used to estimate the next Zernike coefficient and to determine the change in CD. In operation S758, the aberration map of each exposure tool is determined. The measured aberration map has been referenced... Figure 3A , Figure 3B ,or Figure 3C Explanation. In operation S760, the critical dimension cost (CD cost) is defined and the CD cost is optimized for all exposure machine tools T1, T2, T3, and T4. The CD cost (defined in Equation (2)) can be defined as the sum of the CD variation of each slit as an exponential function of each slit. In some embodiments, the CD variation is set to 0 if the CD variation of the slit is within a predetermined threshold. The CD variation is defined in Equation (3). In some embodiments, the predetermined threshold is between approximately 0.05 nm and approximately 0.15 nm for an average CD value of 3 nm. In some embodiments, the threshold is between approximately 1% and 2%.

[0135] In operation S762, if the CD variation in exposure tools T1, T2, T3, and T4 is not within a predetermined threshold, the CD variation is again optimized using aberration maps in operation S760 until the CD variation is within the predetermined threshold. Equation (1) below shows the relationship between the sensitivity table, changes in Zernike coefficients, and the variation in CD values. As shown below, sensitivity is defined in each slit of each grain. As shown below, the change in CD value can be calculated based on the sensitivity table and changes in Zernike coefficients. As shown below, Equation (1) below is defined for one slit (e.g., the first slit), and a similar relationship can be defined for other slits. The first matrix on the left is the sensitivity table (e.g., the sensitivity matrix), which has m values ​​for each slit of the grain for each exposure tool, where m is the number of Zernike coefficients used during optimization. The second matrix in the middle shows the change in the Zernike coefficient of the first slit. The result of multiplying the first and second matrices provides the change in CD variation in the first slit for different exposure tools. In some embodiments, Equation (1) is used for optimization, such that a change in the Zernike coefficient is selected, and the change in the CD value is calculated based on Equation (1). The cost function can be calculated (e.g., recalculated) based on the change in the CD value using the following Equations (2) and (3). Based on the calculated cost function and Equation (1), the change in the Zernike coefficient is determined, and Equations (1) to (3) are recursively calculated. In some embodiments, a lower limit and / or upper limit of the Zernike coefficient is determined, and the selected change in the Zernike coefficient is maintained within the lower and upper limits at each step of the recursive calculation. In some embodiments, the recursive steps are performed until the cost function is less than or equal to a predetermined cost threshold, and the final Zernike coefficient is determined. In some embodiments, the cost threshold is 0. In some embodiments, the recursive steps are performed until the CD variation is within the predetermined threshold defined above, and the final Zernike coefficient is determined. In some embodiments, the development of the photoresist pattern on the substrate is included when calculating sensitivity.

[0136]

[0137] The cost function is defined in equation (2) below. As defined in equation (3), the cost function is the exponential sum of the CD variations of the slit. In some embodiments, the steepest descent is used to minimize the cost function.

[0138]

[0139] in:

[0140]

[0141] As defined above, the CD variation in each slit is the result of subtracting the minimum CD difference among the slits in the multiple exposure tools. When the CD variation is within a predetermined threshold, the CD variation is set to 0. As described above, recursively using equations (1) to (3) can optimize the cost function and make the CD variation in the multiple exposure tools below a specific threshold. Furthermore, the change in the Zernike coefficient can be determined and the final Zernike coefficient can be determined. As described above, the exposure tools can use mirrors or lenses with controllable curvature and position to adjust the wavefront reflected from the mirror or transmitted through the objective lens to adjust the Zernike coefficient by controlling the mirrors or lenses. Therefore, incorporating the change in the Zernike coefficient and achieving the final Zernike coefficient can be performed as described above by moving the mirror up / down, left / right, or forward / backward, tilting at least one mirror, and / or changing the curvature of at least one mirror. In some embodiments, after achieving the final Zernike coefficient, the CD variation of the exposure tools is measured to confirm that the CD variation is within a specific threshold. When the CD variation of the measured exposure machine tool is not within a specific threshold, the Zernike coefficient is adjusted by regression using equations (1) to (3) where the CD threshold is at least 5 percentage points smaller than the specific threshold mentioned above.

[0142] Figure 8A , Figure 8B This disclosure shows key dimensional variations of different exposure machine tools in a system with multiple exposure machine tools, before and after exposure machine tool matching, according to some embodiments of the present disclosure. Figure 8A This displays the maximum CD variation across different exposure tools when the same layout pattern is produced on different exposure tools. As shown in the figure, the grains on the substrate (e.g., grain 470) are divided into 17 slits, and the CD variation (in nm) is determined separately in each slit. Figure 8B The figure shows the maximum CD variation (in nm) of different exposure tools when the same layout pattern is generated on different exposure tools after implementing the above-mentioned exposure tool matching process. As shown in the figure, the CD variation is significantly reduced after matching the exposure tools, especially in the slits near the grain center. As mentioned above, the Zernike coefficient in different slits is adjusted separately.

[0143] Figure 9 Flowcharts illustrating some embodiments of this disclosure of a process 900 for matching multiple exposure machine tools. Process 900, or a portion thereof, may be provided by... Figure 5D The exposure apparatus 200 performs the process. In some embodiments, process 900 or a portion of process 900 is performed by the following references. Figure 10A , Figure 10B The described computer system 700 performs and / or controls. In some embodiments, process 900, or a portion of process 900, is performed by the process described above. Figure 7AA system of multiple exposure machine tools and Figure 7B The system execution that matches multiple exposure machine tools.

[0144] Process 900 includes operation S902, in which the aberration maps of at least two exposure devices of at least two exposure machine tools are determined. As described above, the aberration maps can be determined by... Figure 3A The exposure device 200 determines, or is determined by Figure 3B , Figure 3C The optical systems 300 and 350 are determined. In operation S904, at least one Zernike coefficient of the at least two exposure devices is adjusted based on the aberration maps of the at least two exposure devices to minimize the critical dimension (CD) variation between the at least two exposure devices. As described above, the Zernike coefficient is... Figure 5D The adjustment is made by adjusting the curvature and / or position of at least one of the mirrors M1, M2, M3, M4, or M5 of the projection optical element 204. In some embodiments, mirror M6 is not adjusted.

[0145] As referenced above Figure 5A , Figure 5B , Figure 6A , Figure 6B The Zernike coefficients can be adjusted by moving at least one mirror up / down, left / right, or forward / backward, tilting at least one mirror, and / or changing the curvature of at least one mirror. In some embodiments, the Zernike coefficients Z5 to Z12 of the fifteenth to twelfth Zernike polynomials are adjusted. In some embodiments, the Zernike coefficients Z5 to Z12 are adjusted by moving at least one mirror up / down, left / right, or forward / backward, but without tilting the mirror, to optimize the cost function and make the CD variation in the exposure machine tool less than a specific threshold.

[0146] In operation S906, a photoresist pattern is generated by projecting a first layout pattern onto a respective substrate using the exposure apparatus of at least two exposure machines. For example... Figure 2 As shown, a photoresist pattern is generated by projecting the layout mask of the punctuation mark 205 onto a substrate 210 coated with photoresist. In operation S908, it is determined whether the CD variation in the first region of the photoresist pattern on each substrate is within a threshold. In operation S910, if the CD variation in the first region is not within the threshold, the aforementioned adjustment operation, generation operation, and determination operation are repeated. Figure 7B As shown, if the CD variation is not within the specification, the aforementioned steps are repeated. In some embodiments, the optimization process described above is performed periodically, for example at predetermined times (e.g., once a week) and / or for predetermined number of processes (e.g., number of wafers processed).

[0147] Figure 10A , Figure 10B This illustration depicts instruments used to match multiple exposure machine tools according to some embodiments of the present disclosure. In some embodiments, computer system 700 is used to perform... Figure 2 , Figure 3A , Figure 3B , Figure 3C , Figure 5A , Figure 5B , Figure 5C , Figure 5D , Figure 7A The analyzer module 230, controller 460, and main controller 710 perform their functions. In some embodiments, the computer system 700 controls the brake 351. In some embodiments, the computer system 700 is used to perform... Figure 7B Process 750 or part of process 750, or Figure 9 The manufacturing process is 900.

[0148] Figure 10A This is a schematic diagram of a computer system that performs the functions of an instrument for matching multiple exposure machine tools. All or part of the processes, methods, and / or operations of the above embodiments can be implemented using computer hardware and computer programs executing on the computer hardware. Figure 10A In the computer system 700, there is a computer 701, which includes an optical disk read only memory drive (such as CD-ROM or DVD-ROM) 705 and a magnetic disk drive 706, a keyboard 702, a mouse 703, and a monitor 704.

[0149] Figure 10B This diagram illustrates the internal configuration of computer system 700. Figure 11BIn this computer 701, in addition to the optical disc read-only memory drive 705 and the hard disk drive 706, at least one processor (e.g., a microprocessor unit (MPU) 711), read-only memory (ROM) 712, random access memory (RAM) 713, hard disk 714, and bus 715. The ROM 712 stores programs, such as boot programs. The RAM 713 is connected to the MPU 711 and temporarily stores application program instructions and has a temporary storage area. The hard disk 714 stores application programs, system programs, and data. The bus 715 connects the MPU 711, ROM 712, etc. It should be noted that the computer 701 may include a network card (not shown) for connection to a local area network (LAN).

[0150] The program that causes the computer system 700 to perform the functions of the multiple exposure machine tools in the above embodiments can be stored on an optical disc 721 or a disk 722 and transferred to a hard disk 714. The optical disc 721 and disk 722 are inserted into an optical disc read-only memory drive 705 and a disk drive 706, respectively. Alternatively, the program can be transferred to the computer 701 via a network (not shown) and stored on the hard disk 714. During execution, the program is loaded into RAM 713. The program can be loaded from the optical disc 721 or disk 722, or directly from the network. The program does not need to include, for example, an operating system (OS) or a third-party program, to cause the computer 701 to perform the functions of the controller 460 or the main controller 710 to execute the functions of the multiple exposure machine tools in the above embodiments. The program may only contain an instruction portion to call the appropriate program (module) in controlled mode and obtain the desired result.

[0151] Figure 11A , Figure 11B , Figure 11C , Figure 11D This disclosure illustrates sequential manufacturing operations of methods for manufacturing semiconductor devices according to some embodiments. In some embodiments, at least one exposure machine tool matched with the systems and methods described above is used to manufacture, for example... Figure 11A , Figure 11B , Figure 11C , Figure 11D The semiconductor device shown. (As shown) Figure 11AAs shown, a photoresist layer PR is formed on the target layer TL on the substrate. The photoresist layer PR is sensitive to radiation from the exposure source during subsequent lithography processes. In this embodiment, the photoresist layer PR is sensitive to EUV light used in the lithography process. The photoresist layer PR can be formed on the target layer TL by spin-on coating or other suitable techniques. The coated photoresist layer PR can be baked to remove the solvent from it. Figure 11B As shown, the photoresist layer PR is patterned using an EUV reflective mask as described above. The patterning of the photoresist layer involves a lithography process performed by an EUV exposure system using an EUV mask (e.g., gradation plate 205). During the exposure process, as... Figure 2 As shown, an integrated circuit (IC) design pattern defined on an EUV mask is imaged onto a photoresist layer PR to form a latent pattern on the photoresist layer PR. The patterning of the photoresist layer further includes post-development exposure of the photoresist layer PR to form a patterned photoresist layer PR with at least one opening. In embodiments where the photoresist layer PR is a positive tone photoresist layer, the exposed portion of the photoresist layer PR is removed during the development process. The patterning of the photoresist layer PR may further include other process steps, such as multiple baking steps at different stages. For example, a post-exposure-baking (PEB) process may be performed after the lithography exposure process and before the development process.

[0152] like Figure 11C As shown, the target layer TL is patterned using a patterned photoresist layer PR as an etching mask. In some embodiments, patterning the target layer TL involves applying an etching process to the target layer TL using the patterned photoresist layer PR as an etching mask. The portion of the target layer TL exposed within the openings of the patterned photoresist layer PR is etched, while other portions are not etched. Furthermore, as... Figure 11D As shown, the patterned photoresist layer PR can be removed by wet stripping or plasma ashing.

[0153] According to some embodiments of this disclosure, a method for matching tools includes: determining multiple aberration maps of at least two optical systems of at least two exposure machines, and adjusting at least one Zernike coefficient of the at least two optical systems based on the determined aberration maps of the at least two optical systems to minimize critical dimension (CD) variation between the at least two exposure machines. The method further includes projecting a first layout pattern onto a substrate using the optical systems of each of the at least two exposure machines to generate a photoresist pattern, and determining whether the critical dimension variation in a first region of the photoresist pattern on each of the respective substrates is within a threshold. The method further includes repeating the adjustment, generation, and determination operations if the critical dimension variation in the first region is not within the threshold. In one embodiment, the at least two exposure machines include a first exposure machine, a second exposure machine, a third exposure machine, and a fourth exposure machine. The method further includes minimizing the critical dimension variation in a first region of the photoresist pattern between the respective substrates of the first, second, third, and fourth exposure machines. In one embodiment, minimizing critical size variation includes maintaining the critical size variation below a threshold value of one percent. In one embodiment, the first region is a grain with a length or width between 4 millimeters (mm) and 5 millimeters. In one embodiment, at least two optical systems of at least two exposure machine tools use extreme ultraviolet (EUV) radiation beams to project the first layout pattern onto the substrate, respectively. Each of the at least two optical systems includes a first mirror, and the method further includes moving the first mirror in at least one of the at least two optical systems to adjust at least one Zernike coefficient. In one embodiment, in at least one of the at least two optical systems, the first mirror is moved in one of the following ways: in the propagation direction of the EUV radiation beam, or in a lateral direction (also called a transverse direction) relative to the propagation direction of the EUV radiation beam. In one embodiment, at least two optical systems of at least two exposure machine tools use extreme ultraviolet (EUV) radiation beams to project the first layout pattern onto the substrate, respectively. Each of at least two optical systems includes a first mirror, and the method further includes: adjusting the curvature of the first mirror in at least one of the at least two optical systems to adjust at least one Zernike coefficient.

[0154] According to some embodiments of this disclosure, a method for matching tools includes: determining multiple aberration maps of at least two optical systems of at least two exposure tools; and adjusting at least two Zernike coefficients of the at least two optical systems based on the determined aberration maps of the at least two optical systems to minimize critical dimension (CD) variation between the at least two exposure tools. The method further includes projecting a first layout pattern onto a substrate using the optical systems of each of the at least two exposure tools to generate a first photoresist pattern, and projecting a second layout pattern onto the substrate using the optical systems of each of the at least two exposure tools to generate a second photoresist pattern. The method further includes determining whether critical dimension variations in a first region of the first photoresist pattern and in a second region of the second photoresist pattern on the respective substrates are within thresholds. The method further includes repeating the adjustment operation, the generation of the first photoresist pattern, the generation of the second photoresist pattern, and the determination operation if the critical dimension variations in the first and second regions are not within thresholds. In one embodiment, at least two exposure machine tools include a first exposure machine tool, a second exposure machine tool, a third exposure machine tool, a fourth exposure machine tool, and a fifth exposure machine tool. The method further includes minimizing critical size variations in a first region of a first photoresist pattern and a second region of a second photoresist pattern between the respective substrates of the first, second, third, fourth, and fifth exposure machine tools. In one embodiment, the average critical size value in the first and second regions is 3 nanometers (nm), and minimizing the critical size variation includes maintaining the critical size variation in the first and second regions below a threshold of 0.1 nanometers. In one embodiment, at least two optical systems of the at least two exposure machine tools use extreme ultraviolet (EUV) radiation beams to project a first layout pattern and a second layout pattern onto the substrate, respectively. Each of the at least two optical systems includes a first mirror and a second mirror, and the method further includes moving at least one of the at least two optical systems, at least the first mirror and the second mirror, to adjust at least two Zernike coefficients. At least the first and second mirrors are moved in one of the following ways: in the direction of propagation of the extreme ultraviolet (EUV) radiation beam, or in a lateral direction (also called a transverse direction) relative to the direction of propagation of the EUV radiation beam. In one embodiment, at least two optical systems use extreme ultraviolet (EUV) radiation beams to project a first layout pattern and a second layout pattern onto a substrate, respectively.Each of the at least two optical systems includes a first mirror and a second mirror. Adjusting the at least two Zernike coefficients is achieved by: applying pressure at at least two points on the perimeter of at least the first mirror of at least one optical system to adjust the curvature of the first mirror; and applying pressure at at least two points on the perimeter of at least the second mirror of at least one optical system to adjust the curvature of the second mirror. In one embodiment, the method further includes determining the maximum value of the critical dimension variation in each of the first and second regions of the respective substrates of the at least two exposure machines; determining the minimum value of the critical dimension variation in each of the first and second regions of the respective substrates of the at least two exposure machines; determining the difference between the minimum and maximum critical dimension variations in each of the first and second regions; defining the cost function as the sum of exponential functions of the differences in the first and second regions; and determining the at least two Zernike coefficients by recursively minimizing the cost function. In one embodiment, the method further includes determining a sensitivity map for each of the at least two optical systems of the at least two exposure machines. The sensitivity table contains critical size variations based on the variation of the Zernike coefficient, and the aforementioned sensitivity table recursively minimizes the cost function using at least two optical systems with at least two exposure machine tools.

[0155] According to some embodiments of this disclosure, a system for matching tools includes at least two exposure machine tools, each of the exposure machine tools including an optical system, and each of the optical systems including at least two mirrors. The optical system further includes a controller, an image detector, an analyzer module, and an actuator coupled to the at least two mirrors. In each optical system, the analyzer module is configured to receive an aberration map of the respective optical system from the image detector and to transmit the aberration map of the respective optical system to the controller. In each optical system, the controller is configured to receive aberration maps of the other optical systems. The controller is also configured to adjust at least one Zernike coefficient of the respective optical system, and to adjust at least one Zernike coefficient of the other optical system based on the aberration maps of the respective optical system and the aberration maps of the other optical systems, to minimize critical dimension (CD) variation when at least two exposure machine tools are used in a photo lithography process that projects a layout pattern onto a substrate using an extreme ultraviolet (EUV) radiation beam. In one embodiment, the actuator is configured to move at least one of the at least two mirrors to adjust at least one Zernike coefficient. In one embodiment, at least one of the at least two mirrors moves in one of the following ways: in the direction of propagation of the extreme ultraviolet radiation beam, or in a lateral direction (also called a transverse direction) relative to the direction of propagation of the extreme ultraviolet radiation beam. In one embodiment, an actuator is coupled to the circumference of at least one of the at least two mirrors and configured to apply pressure at at least two points on the circumference of the at least one of the at least two mirrors to change the curvature of the at least one of the at least two mirrors to adjust at least one Zernike coefficient. In one embodiment, the movement of the at least two mirrors includes positional movement in an up / down, left / right, or front / back direction. In one embodiment, the movement of the at least two mirrors includes rotating the at least two mirrors about an axis that coincides with the diameter of the at least two mirrors.

[0156] As described above, the Zernike coefficients of multiple exposure tools are adjusted based on the aberration maps of the exposure tools to match the critical dimensions (CD) of the aforementioned multiple exposure tools, without using standard exposure tools. The mirror is moved to change the beam width of the EUV radiation beam on the scribe plate, thereby limiting the beam width to the range of the scribe plate's layout pattern and avoiding the use of a scribe plate-mask to limit the additional coverage of the EUV radiation beam on the scribe plate. Therefore, the throughput and efficiency of the exposure system can be increased.

[0157] The above description provides a summary of some features of the embodiments, enabling those skilled in the art to better understand the embodiments of this disclosure. Those skilled in the art should understand that they can readily use the embodiments of this disclosure as a basis to design or modify other processes and structures to perform the same purpose and / or achieve the same benefits of the embodiments mentioned above. Those skilled in the art should also understand that such equivalent structures do not depart from the spirit and scope of the embodiments of this disclosure, and that various changes, substitutions, and modifications can be made therein without departing from the spirit and scope of the embodiments of this disclosure.

Claims

1. A method for a matching tool, comprising: Determine multiple aberration maps of at least two optical systems of at least two exposure machine tools; Based on the aberration maps of the at least two optical systems, adjust at least one Zernike coefficient of the at least two optical systems to minimize the critical dimension variation between the at least two exposure tools. By using the optical system described above with each of the above at least two exposure machine tools, a first layout pattern is projected onto a substrate to generate a photoresist pattern. Determine whether the critical dimensional variation in a first region of the photoresist pattern of each of the aforementioned substrates is within a threshold value; and If the aforementioned critical dimension variation in the first region is not within the aforementioned threshold, repeat the aforementioned adjustment operation, the aforementioned generation operation, and the aforementioned judgment operation.

2. The method of claim 1, wherein the at least two exposure machine tools comprise a first exposure machine tool, a second exposure machine tool, a third exposure machine tool, and a fourth exposure machine tool, and the method further comprises: Minimize the critical size variation in the first region of the photoresist pattern between the respective substrates of the first, second, third, and fourth exposure machines.

3. The method of claim 1, wherein minimizing the aforementioned critical size variation comprises: The aforementioned critical dimensional variations should be kept below the threshold of 1 percentage point.

4. The method of claim 1, wherein the first region is a grain with a length or width between 4 mm and 5 mm.

5. The method of claim 1, wherein the at least two optical systems of the at least two exposure machine tools use an extreme ultraviolet radiation beam to project the first layout pattern onto the substrate, wherein each of the at least two optical systems includes a first mirror, and wherein the method further comprises: The first mirror in at least one of the above-mentioned at least two optical systems is moved to adjust at least one Zernike coefficient.

6. The method of claim 5, wherein in at least one of the at least two optical systems, the first mirror is moved in one of the following ways: In the propagation direction of the aforementioned extreme ultraviolet radiation beam; or In the lateral direction relative to the aforementioned propagation direction of the extreme ultraviolet radiation beam.

7. The method of claim 1, wherein the at least two optical systems of the at least two exposure machine tools use an extreme ultraviolet radiation beam to project the first layout pattern onto the substrate, wherein each of the at least two optical systems includes a first mirror, and the method further comprises: The curvature of the first mirror in at least one of the at least two optical systems is adjusted to adjust at least one Zernike coefficient.

8. A method for a matching tool, comprising: Determine multiple aberration maps of at least two optical systems of at least two exposure machine tools; Based on the aberration maps of the at least two optical systems, adjust at least two Zernike coefficients of the at least two optical systems to minimize the critical dimension variation between the at least two exposure tools. A first layout pattern is projected onto a substrate using the optical system of each of the above-mentioned at least two exposure machine tools to generate a first photoresist pattern. A second layout pattern is projected onto the substrate by means of the optical system using each of the above-mentioned at least two exposure machine tools to generate a second photoresist pattern. Determine whether the critical dimensional variations in a first region of the first photoresist pattern and a second region of the second photoresist pattern of the respective substrates are within a threshold value; and If the critical dimension variations in the first and second regions are not within the thresholds, repeat the adjustment, the generation of the first photoresist pattern, the generation of the second photoresist pattern, and the judgment.

9. The method of claim 8, wherein the at least two exposure machine tools comprise a first exposure machine tool, a second exposure machine tool, a third exposure machine tool, a fourth exposure machine tool, and a fifth exposure machine tool, and the method further comprises: Minimize the critical size variation in the first region of the first photoresist pattern and the second region of the second photoresist pattern between the respective substrates of the first, second, third, fourth, and fifth exposure machines.

10. The method of claim 8, wherein an average critical size value in the first region and the second region is 3 nanometers, wherein minimizing the critical size variation comprises: The critical size variation in the first region and the second region is maintained below the threshold of 0.1 nanometers.

11. The method of claim 8, wherein the at least two optical systems of the at least two exposure machine tools use an extreme ultraviolet radiation beam to project the first layout pattern and the second layout pattern onto the substrate, respectively, wherein each of the at least two optical systems includes a first mirror and a second mirror, and wherein the method further comprises: Moving at least the first mirror and the second mirror in at least one of the at least two optical systems to adjust the at least two Zernike coefficients, wherein the at least the first mirror and the second mirror are moved in one of the following ways: In the propagation direction of the aforementioned extreme ultraviolet radiation beam; or In the lateral direction relative to the aforementioned propagation direction of the extreme ultraviolet radiation beam.

12. The method of claim 11, wherein the at least two optical systems use an extreme ultraviolet radiation beam to project the first layout pattern and the second layout pattern onto the substrate, respectively, wherein each of the at least two optical systems includes a first mirror and a second mirror, wherein the adjustment of the at least two Zernike coefficients is achieved by: Pressure is applied at at least two points along the circumference of at least the first mirror of at least one of the aforementioned optical systems to adjust the curvature of at least the first mirror; and Pressure is applied at at least two points on the circumference of at least the second mirror of at least the aforementioned optical system to adjust the curvature of at least the second mirror.

13. The method of claim 8, further comprising: Determine the maximum value of the critical dimension variation in each of the first and second regions of the respective substrates of the at least two exposure machine tools; Determine a minimum value of the critical dimension variation in each of the first and second regions of the substrate of each of the at least two exposure machines; Determine the difference between the minimum value and the maximum value of the critical dimension variation in each of the first region and the second region. A cost function is defined as the sum of exponential functions of the differences between the first region and the second region; and The at least two Zernike coefficients are determined by recursively minimizing the aforementioned cost function.

14. The method of claim 13, further comprising: Determine a sensitivity table for each of the at least two optical systems of the at least two scanner tools, wherein the sensitivity table includes the critical size variation based on the variation of the Zernike coefficient; and The aforementioned sensitivity tables of the aforementioned at least two optical systems using the aforementioned at least two scanner tools recursively minimize the aforementioned cost function.

15. A system for a matching tool, comprising: At least two exposure machine tools, wherein each of the aforementioned exposure machine tools includes an optical system; and Each of the above optical systems comprises: At least two mirrors; One controller; An image detector; An analyzer module; and A brake, coupled to at least two of the aforementioned mirrors; In each of the aforementioned optical systems, the analyzer module is configured to receive an aberration map of the respective optical system from the image detector, and to transmit the aberration map of the respective optical system to the controller; and In each of the aforementioned optical systems, the controller is configured to receive aberration maps of other optical systems, and the controller is also configured to adjust at least one Zernike coefficient of each of the aforementioned optical systems, and to adjust at least one Zernike coefficient of the other optical systems based on the aberration maps of the aforementioned optical systems and the aberration maps of the other optical systems, in order to minimize critical dimension variation when the at least two exposure tools are used in a photolithography process that projects a layout pattern onto a substrate using an extreme ultraviolet radiation beam.

16. The system of claim 15, wherein the brake is configured to move at least one of the at least two mirrors to adjust the at least one Zernike coefficient.

17. The system of claim 16, wherein at least one of the at least two mirrors moves in one of the following ways: In the propagation direction of the aforementioned extreme ultraviolet radiation beam; or In the lateral direction relative to the aforementioned propagation direction of the extreme ultraviolet radiation beam.

18. The system of claim 15, wherein the brake is coupled to the perimeter of at least one of the at least two mirrors and is configured to apply pressure at at least two points on the perimeter of the at least one of the at least two mirrors to change a curvature of the at least one of the at least two mirrors to adjust the at least one Zernike coefficient.

19. The system of claim 17, wherein the movement of the at least two mirrors includes a positional movement in the up / down, left / right, or front / back direction.

20. The system of claim 15, wherein the movement of the at least two mirrors comprises rotating the at least two mirrors about an axis of the at least two mirrors, the axis coinciding with a diameter of the at least two mirrors.

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