TW201802614A - EUV lithography system for dense line patterning - Google Patents

Abstract

Extreme ultra-violet (EUV) lithography ruling engine specifically configured to print one-dimensional lines on a target workpiece includes source of EUV radiation; a pattern-source defining 1D pattern; an illumination unit (IU) configured to irradiate the pattern-source; and projection optics (PO) configured to optically image, with a reduction factor N > 1, the 1D pattern on image surface that is optically-conjugate to the 1D pattern. Irradiation of the pattern-source can be on-axis or off-axis. While 1D pattern has first spatial frequency, its optical image has second spatial frequency that is at least twice the first spatial frequency. The pattern-source can be flat or curved. The IU may include a relay reflector. A PO's reflector may include multiple spatially-distinct reflecting elements aggregately forming such reflector. The engine is configured to not allow formation of optical image of any 2D pattern that has spatial resolution substantially equal to a pitch of the 1D pattern of the pattern-source.

Description

Very short ultraviolet lithography system for dense line patterning [related application]

The present application claims priority from each of the following US Provisional Patent Applications (each and every): 62nd, filed on June 20, 2016, entitled "Dense Line Extreme Ultraviolet Lithography System with Distortion Matching" /352,545; No. 62/353,245, filed on June 22, 2016, entitled "Extreme Ultraviolet Lithography System that Utilizes Pattern Stitching"; and filed on March 24, 2017, entitled "Temperature Controlled Heat Transfer Frame for Pellicle, No. 62/476,476; and No. 62/487,245, filed on April 19, 2017, entitled "Optical Objective for Dense Line Patterning in EUV Spectral Region"; and filed on April 26, 2017, with the title "Illumination System with Flat 1D-Patterned Mask for Use in EUV-Exposure Tool", No. 62/490,313; and "Illumination System with Curved 1D-Patterned Mask for Use in EUV-", filed on May 11, 2017. Exposure Tool, No. 62/504,908. The present application also claims priority from International Patent Application No. PCT/US2017/033637, filed on May 19, 2017, entitled "EUV Lithography for Dense Line Patterning. The disclosure of each of the above-identified patent documents is incorporated herein by reference. Collectively, the above-identified patent documents are referred to herein as prior applications of ours.

The present invention relates to exposure tools for use in lithography processing of semiconductor wafers, and more particularly to patterns that are configured to form parallel lines that are separated from each other by tens of nanometers or less on a wafer. Simplify the exposure tool.

Currently commercially available EUV lithography equipment (hereinafter referred to as a general EUV system) is configured to image a reticle mask carrying any two-dimensional (2D) pattern onto a semiconductor wafer (substrate) On the rectangular area. Prior art EUV systems must be implemented as a scanning system to provide relative displacement between the substrate and the reticle due to the 2D nature of the pattern that must be optically transferred and imaged onto the wafer from the reticle (the scanning system is currently By using a moving stage for the reticle and at least one or more moving stages for the substrate, the reticle pattern is patterned with sufficient accuracy and resolution without the scanning system The transfer of all of the features to the substrate is quite complex and practically not achieved). The structure and operational complexity of currently used systems necessarily and substantially increase operating costs and reduce the number of exposed substrates per unit time, which is partially limited by the transmission of EUV light through the optical system. Furthermore, since pattern transfer requires a process of optical imaging in 2D, the optical element strings of existing general EUV systems require high complexity and are characterized by high complexity. For example, such systems include: six abrasive mirrors in the projected portion of the string of optical elements, wherein the mirror surface roughness is less than 0.1 nanometer rms and the mirror alignment tolerance is less than about 1 nanometer; A structurally complex and adjustable illumination section; and a large reticle or mask with a complex reflective coating. In addition, proper pattern transfer requires the use of a complex combination of alignment marks. All of this inevitably leads to high costs in the design and manufacture of a general EUV system.

Other major issues in ensuring the commercial competitiveness of a generic EUV system (which is well recognized and requires a practical solution) include: (A) from a generic EUV system Insufficient optical power of the EUV source usually equipped. Currently, the typical output is about 40W to 80W. This problem is exacerbated by the fact that the optical power delivered from the EUV source to the reticle by the illumination subsystem of the EUV system is further reduced due to the limited (about 70% per mirror) reflectivity of the EUV mirror. The illumination subsystem is additionally interchangeably referred to as an illumination unit (IU) or an illumination lens (IL). (B) Sensitivity to defects and/or particles on the reticle mask. In fact, since the universal EUV system is configured to image a 2D pattern from the reticle onto the wafer with high resolution, the pattern transferred to the wafer can be easily damaged by defects or particles on the reticle. In other words, each defect or particle on the reticle that is larger than a few tens of nanometers can damage the printed pattern on the wafer. (C) Extremely stringent requirements for the optical aberrations of the projection subsystem imposed by the 2D nature of the arbitrary pattern to be printed and the high resolution. The projection subsystem is additionally interchangeably referred to as a projection optics (PO) subsystem (also known as a projection lens, PL).

Alternatives to current use of EUV lithography processes (and in particular, including the use of Deep Ultraviolet (DUV) light (preferably having a wavelength near 193 nm and using an immersion lens) to multi-pattern the substrate ) can be less expensive but involves complex wafer processing between multiple exposures. Eventually, as the resolution required for the feature increases, the cost of multiple patterning processes will be similar to the point at which the general EUV exposure cost lies.

For any of the above reasons, the use of such universal EUV systems and/or alternative immersion systems for printing patterns having simple geometries is not economically attractive. Therefore, there is a need to configure a simplified EUV system that will not only meet the optometric requirements involved in simplifying the photographic mask transfer onto the imaging transfer on the semiconductor substrate, but also that the cost will be beneficial to the industry.

Specific examples of the invention illustrate a dedicated 1D very short UV (EUV) exposure tool or scriber that is specifically configured to print an array of straight lines on a patterned surface of a substrate. Particular examples additionally provide methods for transmitting radiation via an extremely short UV (EUV) exposure tool and forming an optical image of an object (including an array of straight lines) on the substrate.

In particular, a specific example provides a 1D EUV engraving machine comprising: an EUV source configured to emit EUV radiation; a holder configured to hold a pattern source defining a substantially 1D pattern substantially fixed a workpiece stage configured to move a surface of the workpiece stage relative to a pattern source held by the holder; the IU configured to illuminate the substantially 1D pattern with EUV radiation from the source; A PO subsystem between the IU and the workpiece stage, the PO subsystem being configured to form an optical image of the 1D pattern in the image surface while the image surface is being repositioned by the workpiece stage. In certain cases, the image surface is optically conjugated to a substantially 1D pattern.

A specific example also provides a 1D EUV engraving machine comprising: an EUV source configured to emit EUV radiation; a pattern source carrying a substantially 1D pattern; an IU configured to utilize EUV radiation from the source a substantially 1D pattern; a workpiece stage; and a PO subsystem between the IU and the workpiece stage, the PO subsystem being configured to form in the image surface as the image surface is being moved by the workpiece stage An optical image of a 1D pattern. Here, the PO subsystem includes first and second reflectors, at least one of the first and second reflectors having first and second spatially distinct reflective elements. In one case, the spatially distinct reflective elements are spatially disconnected from one another.

A specific embodiment of the invention also provides a 1D EUV engraving machine comprising an EUV source configured to emit EUV radiation; a pattern source carrying a substantially 1D pattern; an IU, the group of which State illuminating the substantially 1D pattern with EUV radiation from the source; and a PO subsystem configured to reposition the image surface relative to the pattern source and when the image surface is optically conjugated to the substantially 1D pattern, An optical image of a 1D pattern is formed on the surface of the image by a reduction factor N > 1. Here, the reticle is configured such that the 1D pattern has a first spatial frequency, the optical image has a second spatial frequency, and the second spatial frequency is at least twice the first spatial frequency.

114‧‧‧Light source

118‧‧‧First reflector

122‧‧‧second reflector

126‧‧‧Relay reflector

130‧‧‧ first mirror

130A‧‧‧Center Coverage

134‧‧‧second mirror

134A‧‧‧ center cover

140‧‧‧ radiation

144‧‧‧ pattern source

144'‧‧‧ pattern source

148‧‧‧radiation

152A‧‧‧beam

152B‧‧‧beam

156‧‧‧ wafer

156A‧‧‧ wafer stage

160‧‧‧ aperture

160'‧‧‧ Field of view

164‧‧‧Photonics/Aperture

200‧‧‧ illuminator

210‧‧‧ reflector

210-i‧‧‧ individual reflectors

210-j‧‧‧ individual reflectors

214-A‧‧‧radiation source

214-B‧‧‧radiation source

220‧‧‧ reflector

220-i‧‧‧ individual reflectors

220-j‧‧‧ individual reflectors

300‧‧‧Achromatic astigmatism optics two-mirror system

310‧‧‧ primary mirror

320‧‧‧ primary mirror

320‧‧ ‧ mirror

510‧‧‧radiation beam

810‧‧‧Rhombus shaped exposure field

820‧‧‧ hexagonal shape exposure field

830‧‧‧ concave polygon exposure field

910‧‧‧ Collector

910A‧‧‧Center opening

914‧‧‧ Tin ejector

916‧‧‧Auxiliary light source IF

918‧‧‧ Plasma

1210‧‧‧ arrow

1220‧‧‧ normal

Main reflector of the M1‧‧‧PO subsystem

M1-A‧‧‧reflecting element

M1-B‧‧‧reflecting element

Auxiliary reflector for the M2‧‧‧PO subsystem

M2-A‧‧‧reflecting element

M2-B‧‧·reflector

The invention will be more fully understood by reference to the following detailed description, in which <RTIgt; </ RTI> <RTIgt; </ RTI> <RTIgt;

2A is a side view illustrating a schematic view of a specific example of a lighting unit configured in accordance with the inventive concept; FIGS. 2B, 2C are schematic views showing a reflector of the specific example of FIG. 2A in a front view; FIG. 2D illustrates a specific embodiment of FIG. 2A A first-order layout of an example in which the reflector is replaced by an equivalent lens; Figure 3A shows a specific example of a projection optics design; Figure 3B lists a Rennick parameter of the design of the projection optics (PO) of Figure 3A; Figure 4A, 4B illustrates a determination and correlation system for pupil parameters for a specific example of the present invention; FIG. 5 presents an alternative embodiment of the system of the present invention; and FIG. 6 shows a specific example of a system from the present invention under specified conditions. A diagram of the required radiation-power output of the light source used together; Figure 7A provides a standard high NA 2D EUV tool for specific examples and prior art of the present invention Data output from the resist model by focusing on the optimal dose; Figures 7B, 7C provide pattern features formed by photolithography using systems employed in the prior art and systems configured in accordance with embodiments of the present invention Comparison of Critical Sizes; Figures 8A, 8B, and 8C illustrate examples of the shape of an exposure field formed at the image surface by the system of the present invention. Each region of the image surface is last scanned twice (along the arrow as shown); Figure 9A illustrates having a specific example for refocusing EUV radiation from the LPP to IF (IF again serves as the IU for use in the present invention) The light source of the ellipsoidal mirror of the laser drives the configuration of the light source of the plasma source. For comparison, a 5sr collector and a 1.6sr subaperture configuration are schematically shown; FIG. 9B is a laser driven plasma of FIG. 9A illustrating a collector 910 having a central opening 910A, a tin ejector 914, and an auxiliary source IF 916. Schematic diagram of the source based on the ray model; Figures 9C, 9D illustrate the assumed substantially Gaussian distribution of the plasma of the laser driven plasma source according to the model used for the calculation; Figures 10A, 10B illustrate, respectively, along the optical axis The angle distribution of the radiation of the laser-driven plasma source model viewed downward and the angular distribution of the radiation of the same source in the identified cross-sectional plane transverse to the optical axis; FIGS. 11A and 11B respectively illustrate the passage of the auxiliary light source The distribution of the rays produced by the modeled laser driven plasma source and the cosine of the directions of the rays from the plane of the convergence point of the radiation reflected by the collector of the plasma source; FIG. 12 schematically illustrates an idea in accordance with the present invention Part of an optical component string of an alternative example of a 1D EUV exposure tool; Figure 13A schematically illustrates a perspective view of a particular implementation of a specific example of a PO subsystem in which at least one of the primary and secondary reflectors is configured in accordance with a plurality of reflective elements comprising spatially different from each other; Figure 13B is a The schematic of the diagram of Figure 13A is complemented by the symmetry of the configuration of the multi-reflective element reflector depicting the PO subsystem relative to the direction of extension of the elements of the 1D pattern of the pattern source.

The size and relative proportions of the elements in the drawings may be set to be different from the actual size and proportions to appropriately facilitate the simplicity, clarity and understanding of the drawings. For the same reason, not all of the elements that are present in one figure may be shown and/or labeled in another figure.

In accordance with a preferred embodiment of the present invention, an EUV exposure tool and method is disclosed for applying a new one-dimensional pattern containing spatially densely packed parallel lines to a selected substrate (and in certain cases - has carried light micro Photolithographic marking is performed on the patterned image and the substrate of the spatially distorted pattern in a particular case.

As used herein, and unless otherwise specified, the term "one-dimensional pattern" (or "1D pattern") is defined on the surface of a light mask or reticle (for transfer to a selected substrate using photolithography). A photosensitive photoresist (such as a semiconductor wafer) to create an image of the 1D pattern and generally extends across a geometric pattern of the surface along two axes transverse to each other. The 1D pattern can vary along the first axis of the pattern while the remaining ones are substantially constant along the second axis (ie, the 1D pattern can be characterized by geometric variations along the second axis, the values of the geometric variations not exceeding the edge 50% of the change observed on the first axis, preferably no more than 20% of the change observed along the first axis, more preferably no more than 10% of the change observed along the first axis, or even more Preferably within 5% or less of the change observed along the first axis, and optimally within 1% or less of the change observed along the first axis). 1D An example of a pattern is provided by any collection of spaced apart substantially identical, parallel, elongated pattern elements, such as a combination of straight parallel lines or slits in an additional opaque screen defined at the light mask. In a particular case, a nearby 1D pattern may form a linear (1D) characterized by a periodic variation amplitude along a first selected axis and a constant amplitude along a second axis selected to be transverse to the first axis. A grating (such as a 1D diffraction grating). Additionally, as will be appreciated by those skilled in the art, the 1D pattern can still have small variations along the first axis and/or the second axis in order to correct imaging distortion caused by deformation of the optical system or substrate. For the purposes of this disclosure, an element or component that contains a substantially 1D pattern (and regardless of the particular configuration of the element or component, for example, whether as a reticle or mask) is interchangeably referred to as a pattern source.

In contrast, the term "two-dimensional pattern (2D pattern)" is defined to mean a collection of pattern elements that must be defined along two mutually transverse axes. One of the simplest examples of 2D patterns is provided by a grid or grid (which forms a 2D raster when the grid or grid has a spatial period defined along two transverse axes). Regarding the pattern of the light mask of the reticle as disclosed herein, the 1D and 2D patterns are considered to be the same regardless of the curvature of the surface of the substrate (or light mask) on which the 1D and 2D patterns are formed. For simplicity, the EUV system of the present invention (where specific examples of objective lenses discussed herein are intended to be used) is specifically and purposefully configured for imaging a 1D reticle pattern, and is referred to herein as a 1D EUV system. For simplicity and in contrast, an EUV system (such as a general EUV system) configured to provide imaging for a 2D patterned reticle may be referred to as a 2D EUV system.

A specific example of the present invention provides a solution to the compounding of the practical problems encountered in the prior art by using a 2D EUV system:

- Configured to print 10 nm (and smaller) in the manufacture of advanced semiconductors The cost-effective lithography method of the periodicity of the spacing and the current unavailability of the system utilize spatially dense patterns that are configured to optically image high quality linear gratings by using the following: The design of the EUV exposure tool interchangeably referred to as "dense line"): 1) EUV light; 2) reticle, which (on the appropriate reticle stage) is configured to (2i) in relative Positioning in a substantially fixed relationship between the illumination and projection subsystem of the exposure tool, and (2ii) contrasting with the general EUV system, not scanning, and (2iii) carrying a substantially linear diffraction grating (which may be an amplitude grating) Or phase grating); 3) a projection optical system having an NA of 0.40 to 0.60 and an obstruction of 20% to 40% (in terms of NA; the pupil obstruction is thus a square value); and 4) scanning the wafer stage.

- The problem of lack of proper matching between the image of the reticle pattern and other patterns already present on the wafer is caused by proper adjustment of the scanning trajectory of the wafer stage, and by scanning and exposure of the crystal The optical magnification and "magnification tilt" of the reticle pattern are reasonably changed during the circular process (the latter term indicates a linear change in magnification across the exposure field), which is solved by using the 1D EUV system of the present invention. In this case, the problem of geometrically matching the continuous scanning exposure field with the distortion of the layer printed using conventional tools (the operation of the conventional tool produces discontinuities between adjacent pictures) is by scanning the wafer on the wafer as appropriate. Each time, it is solved by exposing every other screen in the first pass and exposing the candidate screen in the second pass.

- persistence of insufficient quality stitching between directly adjacent exposure fields formed on the wafer by locating one of the reticle, wafer, and intermediate image planes and properly shaped to span The entire exposed area of the wafer is created by a spatially uniform, regular exposure pattern defining the "blind" field of view of the perimeter of the individual exposure fields to be included in the 1D EUV system of the present invention. In certain cases, the blind field stop contains an aperture having a polygonal perimeter.

- The persistence problem of insufficient illumination levels commonly used for exposure tools utilizing EUV light is provided by providing first and second reflectors with (1) an array containing polyhedral fly's eye reflectors and (2) The illumination optics assembly of the relay mirror between the reflectors and the reticle is addressed in the dense line 1D EUV lithography system of the present invention. In this 1D EUV system, the shape of one of the fly's eye array reflectors preferably matches the projection optics assembly optimized for the two-beam interference across the entire range of pitch values characterizing the 1D mask pattern. The shape of the entrance pupil.

- The persistence problem of insufficient illumination levels commonly used for exposure tools utilizing EUV light is provided by providing first and second reflectors with (1) an array containing polyhedral fly's eye reflectors and (2) its surface A reticle having a finite radius of curvature (i.e., curved) and having a substantially linear diffraction grating pattern thereon is addressed in the dense line 1D EUV lithography system of the present invention. In this 1D EUV system, the shape of one of the fly's eye array reflectors preferably matches the projection optics assembly optimized for the two-beam interference across the entire range of pitch values characterizing the 1D mask pattern. The shape of the entrance pupil. Additionally, this 1D EUV system is designed to image, each reflector of one of the fly's eye arrays to a projection optic optimized for two-beam interference across the entire range of pitch values characterizing the 1D mask pattern The entrance pupil of the assembly.

Implementation of the inventive concept provides for being configured to optically achieve high resolution in a cost effective manner (in this case, the periodic line pattern (for example) corresponds to a pitch or period of ten to twenty nanometers, Preferably less than 10 nm, more preferably a few nanometers (for example) 5 nm or less) transfer dense line pattern to achieve 10 nm and 7 nm node semiconductor devices (according to the international technology roadmap for semiconductors) Exposure tools or machines as defined by (ITRS 2.0). The idea of the present invention stems from the fact that modern high-density semiconductor wafer designs are increasingly based on 1D geometric patterns. understanding. A specific example of a 1D EUV system of the present invention (specifically configured to optically image a 1D pattern from a reticle, such as a pattern representing a 1D grating, to a substrate of interest) has a transparent structure that is superior to a universal 2D EUV system and The operational advantages are due to:

- The optical system of the 1D EUV system is substantially simplified compared to the optical system of the 2D EUV system and may be able to include fewer mirror surfaces, which in effect utilizes the smaller optical power required from the light source (eg tens of watts, in In one example, as low as about 20 W) provides good quality exposure.

- due to the 1D nature of the reticle pattern to be transferred onto the semiconductor wafer, (a) there is no longer a need to scan the reticle stage relative to the wafer stage; therefore, the light of the specific example of the invention The hood stage or support does not include a scanning stage having a long mechanical stroke; (b) in certain instances, the reticle pattern defines a linear grating and can be substantially linearly diffractive grating (binary pure amplitude grating, Or a pure phase grating). In a particular implementation in which the reticle is formatted as a phase grating, the diffraction efficiency of the 1D EUV system is greatly improved, thereby increasing the effective product yield; (c) the optical imaging of the 1D reticle pattern is reduced to (Basically) 1D imaging - that is, since the spatial variation of the image formed on the resist carried by the substrate exists only in one direction, the 1D EUV system requires more relaxed requirements for the optical aberration of the PL ( Compared to the requirements of the conventional 2D EUV system).

- The cost of the proposed EUV grating machine can be much lower since the optical element string of the system eliminates some or even multiple optical surfaces (compared to a 2D EUV system) to scan the reticle stage, film and other components.

- It is also understood that since the exposure at any point on the wafer is the result of the integration of light across the reticle at different points across the reticle, smaller defects on the grating pattern of the reticle And the particles do not significantly affect the exposure. For example, micron-sized particles or pattern defects on the reticle will destroy the fidelity of images printed by the 2D EUV system, but for 1D EUV systems (where the size of the exposure field is a few centimeters or more) will only be produced Negative changes in exposure dose.

In accordance with the teachings of the present invention, a specific example of a 1D EUV system is at least configured to perform an operation - utilizing an EUV light source configured to deliver at least 20 W optical power to an IU having a central leaf shaped monopole illumination pattern; In the case where the distance of the image formed in the resist is 20 nm or less and without printing any alignment or field kerf marks, the 1D pattern is in a predefined direction (as appropriate, in order to facilitate The different layers are exposed in different orientations (eg, the vertical orientation of a given 1D pattern on the first layer and the horizontal orientation of the 1D pattern on the second layer), the substrate can be rotated 90 degrees for exposing some layers) Medium-reflective or transmissive reticle optical imaging onto a substrate (preferably having a diameter of 300 mm or greater); - by using a center of 40% or less having a NA and NA of 0.4 or greater And a yield of 50 wafers (wph) at least every hour at an irradiation dose of about 30 mJ/cm 2 (as measured at the wafer plane) (preferably 70 wph; more preferably 100 wph; More preferably, the PL of greater than 100 wph)) defines the operation of the lithographic exposure substrate. In one implementation, the exposure field (on the substrate) is configured as a diamond for reliable and repeatable stitching of directly adjacent fields; - in one implementation, optical adjustment via mag-tele shift; and - Ensure that the overlay between the printed and underlying layers has an average +3 sigma value of 1.7 nm or less.

The specific details, parts, and components of the entire system are prioritized in several The disclosures of the above-identified applications (collectively referred to above as commonly referred to as "the prior application of the present invention"), the disclosure of each of the prior applications are hereby incorporated by reference.

General illustration of a specific example of a 1D EUV system

A generalized schematic diagram of a specific example 100 of a 1D EUV system configured in accordance with the teachings of the present invention is shown in FIGS. 1A and 1B. The system can include one or more EUV sources (such as a light source 114 that operates, for example, at a wavelength of 13.5 nanometers). The system includes: an optical illumination subsystem or unit (IU) including a first reflector 118 and a second reflector 122 and a relay reflector 126; and a PO subsystem comprising two or more than two reflective reflectors A mirror, at least one of the mirrors having an area defining an optical obscuration (the two mirror objective is shown to include a first mirror 130 and a second mirror 134, each containing a corresponding center obscuration 130A, 134A). The term optical obscuration is used herein to mean at least a portion of (of the optical element) within which the further transmission of light incident on the optical element to the optical element in the next line is prevented or even blocked. A non-limiting example of obscuration in the case of a reflective objective as shown is provided by (i) a through opening in a substrate of a curved mirror (such as a curved primary mirror 130A) within its boundaries, incident thereon The light on the mirror is not further reflected toward the curved auxiliary mirror 130B but is actually transmitted through the through opening, and (ii) the absence of a reflective coating in a predetermined region of the mirror (substantially defining the same optical effect). The term center obscures defines an obscuration centered on the optical axis.

Reflector 118 collects radiation 150 emitted by light source 114 and transmits radiation 150 as radiation 140 to relay mirror 126 via reflections exiting reflector 122. The system further includes a pattern source 144 (configured as a reticle in this example) disposed in the optical communication with the IU and PO. The pattern source 144 carries a spatially dense 1D pattern and is positioned to illuminate with radiation 148 that is delivered from the light source 114 and reflected by the relay reflector 126 to the pattern source 144 via the mask 134A. Such as As shown, pattern 144 is a light mask that operates in reflection (in a related embodiment, the reticle can be configured as a transmissive mask, as appropriate). It is also contemplated that depending on the particular implementation of system 100, the substrate surface of pattern source 144 on which the 1D pattern is carried may be curved (in this case, the reflective pattern source has non-zero optical power and may be referred to as a curved pattern) Source) or flat (in this case, the reflective pattern source has zero optical power and can be referred to as a flat pattern source).

In addition, the 1D pattern on the reticle can be distorted in a manner that compensates for the undesirable distortion of the PO. When the 1D pattern carried by the reticle is configured as a suitably sized linear diffraction grating, the pattern source 144 diffracts the radiation 148 incident thereon to form a diffraction comprising the spatially distinct beams 152A, 152B. The beams, beams 152A, 152B represent diffraction orders (in one example, +1 and -1 order diffraction), respectively, and propagate toward the mirror 130 of the PO (zero-order diffraction can be appropriately blocked so as to propagate), in this technique A known). In combination, the first reflector 130 and the second reflector 134 of the PO redirect the diffracted beam onto the workpiece or substrate 156 via the mask 130A to expose an image of the 1D pattern on which the pattern source 144 is carried. At least one layer of photoresist. It will be appreciated that in accordance with the teachings of the present invention, the reticle is disposed in substantially fixed spatial and optical relationship with respect to the IU and PO subsystems, as both the position and orientation of the reticle are selected and defined in the 1D EUV. The interior of the exposure tool is fixed (except for optional small adjustments that may be required to maintain focus and alignment). The term "substantially fixed" refers to and is defined in a component (eg, a reticle whose mechanical support is not configured to synchronize with the motion of the workpiece-stage or wafer-stage during operation of the exposure tool. The position of the structure of the ground scanning or moving reticle can still undergo a small adjustment (the amount of adjustment is sufficient to correct the error in any of focusing, magnification and alignment during operation of the exposure tool) and/or situation.

The system may also include: proper placement in the IU (as shown in the mirrors 122, 126) Between the fixed size or variable aperture 160 (eg, a variable slit of a particular shape; interchangeably referred to as "pattern blind" or "blind field stop" or simply "field stop" a stop diaphragm or aperture 164 (a desired size to match the desired shape of the entrance pupil of the PO); a stage/mounting unit supporting the reticle (not shown); a wafer stage 156A equipped with appropriate A stage mover (not shown) to provide for scanning of wafer 156 relative to pattern source 144 and beams 152A, 152B in accordance with a lithography exposure process; and other auxiliary components as desired (eg, vacuum chambers, metrology systems, and Temperature control system). The x-axis is defined to be perpendicular to the axis along which the scan is performed during system operation, while the y-axis is defined to be parallel to this scan axis. In the particular example shown in Figures 1A, 1B, the 1D pattern includes lines parallel to the Y-axis.

Different variations of the proposed implementation are within the scope of the invention. For example, FIG. 5 schematically illustrates a specific example 170 of a 1D EUV system in which the relay mirror 126 has been removed as compared to the specific example 100 of FIG. 1B. This 1D EUV system without relay reflectors is discussed in more detail below. Figure 12 provides an illustration of yet another alternative implementation of an optical element string of a 1D EUV system in which the pattern source (shown as 144' and having a non-zero curvature of the surface carrying the substantially 1D pattern) is off-axis illumination, as discussed below .

Referring again to FIGS. 1A and 1B, the 1D EUVD exposure tool is additionally supplemented by a control unit (control electronics), optionally equipped with a programmable processor and configured to control at least the wafer-stage (and in some In a specific example, operation of at least one of a light source, an IU, and a PO subsystem. (For the sake of simplicity, Figures 5 and 12 do not describe the control unit.)

Example of a lighting unit (IU)

In accordance with the teachings of the present invention, in one example of a specific example, the IU as a whole is configured to be operatively corresponding to the following and more detailed in our prior application. A specific example of a 2-mirror (or in a related embodiment, 3-mirror) astigmatic lens PO discussed and works optically with a specific example of the PO, and may include at least a "flying eye" structure A reflector unit. One implementation of the IU design assumes a 16.5 mm wide diamond exposure field on the image surface (eg, the surface of a workpiece such as a wafer placed on the upper wafer-stage in a particular case), which achieves an exposure field Correctly stitched. It is also assumed and implemented that the zero-order diffracted beam formed at the substantially 1D pattern of the pattern source 144 is blocked such that optical interaction of the +1 and -1 order beams of the optical image of the substantially 1D pattern is formed at the image plane. Double the spatial frequency of the 1D pattern in the optical image and also allow for near normal incidence illumination. (When needed, it can be obscured by the center in the PO, or as discussed elsewhere in this application, by using a dedicated radiation blocking element to achieve proper blocking of the zero-order diffracted beam.)

A schematic representation showing some details of one specific example of an IU is shown in Figures 2A, 2B, and 2C. Additional details and/or specific examples are disclosed in our prior application. A particular example of illuminator 200 is configured to operate with a plurality of EUV radiation sources (discussed below) and provide: - a reasonably defined illumination pattern whose shape is selected for maximum incoherence of light, the maximum incoherence Sex does not provide contrast loss for straight line arrays that form pitches of tens of nanometers (eg, 20 nanometers to 30 nanometers). For example, the IU and the pattern source operatively cooperate to form an illumination pupil defined by the intersection of two planar shapes, such as a shape defining a plan view, in a particular implementation - two circles or discs (for PO subsystem). The goal of maintaining the highest possible contrast is achieved by directing all EUV radiation collected by the IU from the EUV source within the boundaries of the illumination pupil thus defined; - two first of the individual reflectors 210 that may have a diamond perimeter Fly eye reflex Devices FE1-A and FE1-B, as shown in Figure 2B; and - a second "fly-eye" reflector array FE2, which is assembled from a block formed by a reflector 220 (having a hexagon or a ring perimeter) State to define a leaf-shaped aperture B24 and to effectively combine radiation inputs LA, LB received from a plurality of radiation sources 214-A, 214-B while conserving optical expansion, and - a curved relay mirror as part of the illumination unit; reflector Each of the fly's eye arrays (FE1-A, FE1-B, FE2) is configured to capture by a corresponding two-dimensional array using mirrors (alternatively referred to as "facets" or "eyes") And reflected from the radiant energy obtained by the corresponding radiation object. This array of mirrors or facets can often be referred to as a "fly eye reflector" (or even a fly-eye lens) without the aid of an additional larger inspection lens and/or reflector, as is sometimes the case in the art. So called). As shown, light from source 214-A is captured by reflectors FE1-A; light from source 214-B is captured by reflectors FE1-B; light reflected by FE1-A and FE1-B is captured by FE2. Each individual mirror forms an image of the radiation object as seen from the viewpoint of the individual mirror position. In other words, there is one unique element in FE1-A or FE1-B (but not simultaneously) associated with each element of FE2. Thus, as configured, each of the individual mirrors FE1-A and FE1-B have respective mirrors in the FE2 array. For example, the individual reflectors 210-i of the array FE1-A form an image of the light source 214-A at the individual reflectors 210-i of the array FE2, while the individual reflectors 210-j of the array FE1-B are in the array FE2 An image of light source 214-B is formed at individual reflectors 210-j.

In the design discussed above, there are only three sequential reflections of the light beam propagating via the illuminator, as compared to the more complex designs of the prior art, and since each mirror typically has a reflectivity of only 65% to 70% This results in a significant improvement in optical transmission. With universal EUV machines The number of reflections is about half compared to the prior designs used in the present invention, so the amount of light transmitted by the IU of the specific example of the present invention is approximately doubled compared to the amount of light of the general EUV system. In fact, the transmittance through the system can be estimated as a value of X^N, where X is a typical reflectance (65% to 70%) and N is the number of reflections. In conventional general systems, the IU has at least five (or more than five) mirrors, while specific examples of the invention include as few as three mirrors. Thus, IU transmission from 11% to 17% (for a universal EUV system with 5 mirrors) is increased to 27% to 34% for a particular example of the invention. Even more pronounced after considering the PO subsystem, the PO subsystem uses about six mirrors in a general EUV system and only two mirrors are used in the specific example of the invention. In this case, the transmittance of 0.9% to 2% for a typical universal EUV system including transmission via IU and PO, but without the presence of a reticle, is increased by an order of magnitude to 12% when using a specific example of the present invention. To 17%.

的光學擴展，其中N_FE為FE2陣列中的個別鏡的數目(及FE1-A及FE-B中的個別鏡的總和)。 Referring further to Figures 1, 2A, and 2B, a first-order layout of the IU is schematically illustrated in Figure 2D, wherein the mirror elements (each having a specified surface area ai and focal length fi) are depicted as equivalent lens elements for simplicity of illustration. . In general, it should be understood that multiple arrays of FE1 mirrors are used to multiplex light received from multiple sources to provide an IU equal to

Optical expansion, where N _FE is the number of individual mirrors in the FE2 array (and the sum of the individual mirrors in FE1-A and FE-B).

In fact, the number of individual mirror elements in the FE2 array can be determined based on considerations of the desired uniformity of light at the reticle 144 and the filling of the entrance pupil of the PO. In one particular embodiment, the FE2 mirror array includes 98 hexagonal elements 220 (as shown in FIG. 2C), each of which has an angular width of 0.01996 radians as seen from the location of wafer 156. The solid angle of each of the 220 elements (as seen from the wafer) is 3.451e ^-4 steradian, which results in an optical expansion of the element of 0.04698 mm ² sr (for a regular diamond field of 16.5 mm width) (associated with each of the 220 elements), and the total optical spread of 4.604 mm ² sr for the entire FE2 array.

The angular size of the individual elements 210 of the array FE1-A (or FE1-B, each having 98/2=49 individual micromirror elements) can be used to understand the angular size of the individual components of the FE2 array and the size of the source. Under evaluation:

分別表示FE1及FE2的個別鏡元件所對的角度。雙撇號表示其為所成像所對的角度。L表示自光瞳至影像平面的距離，且d _S 表示自源至FE1的距離。 Where δθ ₁ ,

The angles of the individual mirror elements of FE1 and FE2 are respectively indicated. The double apostrophe indicates that it is the angle at which the image is imaged. L represents the distance from the pupil to the image plane, and d _S represents the distance from the source to FE1.

To complete the evaluation of the first-order design of the 1D EUV system, a free parameter is additionally selected: in one particular implementation, the distance from the source to the corresponding FE1 array is selected to be t ₀ = 500 mm; the relay mirror 126 and the grating mask 144 are separated. The distance is selected to be t ₃ =1 m, and the distance between the FE2 array and the relay mirror 126 (corresponding to the unit magnification imaging case) is t ₂ = t ₃ + t ₄ . The distance from FE1 to FE2 is about ₁ 872 mm of t ₁ = d ₂ * t ₀ / d _S . It should be appreciated that other sets of free parameters can be used to design related specific examples.

In addition, the lateral dimensions of the FE1-A, FE1-B, and FE2 arrays are set as follows: - FE1 width (corner-to-corner angle): d ₁ = t ₀ δθ ₁ = 39.7 mm; - FE2 width (flat shape of hexagon) To the flat size): d ₂ =d ₂ p*t ₂ /(t ₃ +t ₄ )=7.24 mm; the total size across the FE1-A (or FE1-B) array is 8 elements, in each case in the specific example One is 39.7 mm wide (corner to corner), as shown in Figure B-2, totaling approximately 317.6 mm wide in the x direction, or 9 along an axis inclined at 45 degrees with respect to the x-axis in Figure B-2. *39.7/sqrt(2) = 252.65 mm wide. In general, the width of the FE1 array along the x-axis is generally between 10 mm and 300 mm.

Width of the FE2 array: In the particular implementation of Figure 2C, there are seven individual 220 mirror elements spanning the array, each being 7.24 meters wide, resulting in an FE2 array having a width of 50.68 millimeters along the x-axis as shown. However, in general, the "waist" of the FE2 array is between 10 mm and 300 mm, preferably between 30 mm and 70 mm.

The width of the relay mirror 126 is 1 meter away from the mask 144, and the relay mirror 126 is opposed to 0.125*0.429 radians in the x direction and the y direction. Under certain conditions, the reticle 144 is 6*16.5=99 mm wide (corner to corner), resulting in a 215 mm by 520 mm size of the relay mirror 126. However, in general, the size of the relay mirror 126 is in the range of 100 mm by 700 mm and 300 mm by 400 mm.

3.147m ^-1；一般而言，在0.01屈光度與100屈光度之間；(B)對於中繼鏡126：在一個具體實例中

0.6299m^-1；(C)對於陣列FE2：在一個具體實例中

1.3171m ^-1；大體在0.01屈光度與100屈光度之間。應理解，術語光功率為透鏡、鏡或其他光學系統的特性，其界定此系統會聚或發散入射於其上的光的空 間分佈所達到的程度。光功率的量測值等於與光學系統的焦距值互逆的值。 In one specific example, the optical power of the mirror is selected as: (A) for array FE1: in a particular embodiment

3.147 m ^-1 ; in general, between 0.01 diopter and 100 diopter; (B) for relay mirror 126: in a specific example

0.6299m ^-1 ; (C) for array FE2: in a specific example

1.3171 m ^-1 ; generally between 0.01 diopters and 100 diopters. It should be understood that the term optical power is a characteristic of a lens, mirror or other optical system that defines the extent to which the system converges or diverges the spatial distribution of light incident thereon. The measured value of the optical power is equal to the value reciprocal to the focal length value of the optical system.

It should be appreciated that the proposed specific example of the IU provides an image plane between the FE-2 reflector 122 and the relay mirror 126. This plane is optically conjugated to both the reticle 144 and the plane of the wafer 156 and provides the proper position to position (as the case may be) the aperture 160 to control the dose of radiant power delivered to the reticle 144 and define it on the wafer. The boundary of the exposure field formed at the location.

Additional relevant specific examples of IUs configured in accordance with the inventive concept (and in detail, specific examples configured to operate with a single EUV only radiation source) are in our prior application (and in detail, in This is discussed in U.S. Provisional Application Nos. 62/490,313 and 62/504,908.

Example of a projection optics subsystem

In one specific example, a 1D EUV system for projection lithography is configured to employ a PO portion that includes a 2-mirror system. The PO portion is supplemented by a reticle carrying a substantially 1D mask pattern on a flat surface (eg, the reticle is formed by defining a 1D reflective diffraction grating on a planar juxtaposed substrate). The PO in this particular example is configured to include a 2-mirror, unipolar (i.e., light distribution at any pupil plane containing a "pole" or illumination area) illumination subsystem. In a related embodiment, the PO includes a 3-mirror astigmatism lens.

In one particular implementation shown in FIG. 3A, for example, a 1D EUV system includes a 6x reduction or reduction configured (due to imaging, reticle pattern), NA = 0.4, and 16.5 mm on the wafer. (diameter) by 5 mm diamond exposure (16.5 mm means the field width in the X direction perpendicular to the scanning direction; 5 mm means the field length in the Y direction, and the Y direction is parallel to the scanning line and the wafer stage scanning motion Optical imaging of the astigmatism projection optics in the case of a two-mirror system 300, when using coaxial illumination, the aberration within the diamond exposure is Small (about 12 mm wave or less). The selected shape of this diamond exposure field is suitable for stitching the adjacent field. The primary mirror 310 of this design has a diameter of approximately 583 millimeters. The aspherical distribution of the mirrors 310, 320 is primarily rotatably symmetric with minimal astigmatism. In the case of coaxial illumination, the 彗-shaped nick item is not used, but in the specific case where the illumination is off-axis, the 彗-shaped nick item can be introduced. The system further utilizes a flat reticle that is separated from the auxiliary mirror by a distance between about 800 mm and 2000 mm (as shown - about 1400 mm). The entrance pupil of system 300 is about 2.175 meters from the reticle of the 1D EUV system (near the wafer/substrate) while the distance from the reticle to mirror 310 is about 1 meter. The parameters for the simulated Nickel aberration for the simulation of system 300 are listed in Figure 3B). In the 1D EUV system thus implemented, the light beam from the light source undergoes interaction with only six reflectors after propagating towards the target substrate (two reflections at the IU's reflector array and one reflection at the relay mirror) a reflection at the reflective reticle; and two reflections at the mirror of the PO), thereby reducing the optical power loss after reflection compared to the 2D EUV system, and thus reducing the output power for the EUV source How high is the requirement. (Actually, in a typical 2D EUV system, the beam is reflected at least twelve times or more by the reflector forming the string of optical elements of the system.)

Since the pattern on the reticle contains a 1D grating, the incident light is roughly diffracted in the XZ plane. Thus, each of the mirrors 310, 320 can be configured as two separate segments that provide the necessary portion of a theoretically continuous toroidal curved reflective surface.

In a related embodiment, another flat field 6x reduction is implemented using a primary mirror having a diameter of 835 millimeters and other components as described above, at which time the field diameter is expanded to a field diameter of 26 millimeters.

In another related embodiment, the combination is on a curved substrate (ie, on a surface of a substrate having a non-zero curvature value (and thus a finite radius of curvature); for example, in a concave surface The reticle that defines the 1D mask pattern utilizes a 2 or 3 mirrored PO subsystem. The wavefront curvature of the radiation incident on the reticle changes after interacting with the reticle.

In general, the PO subsystem has a reference axis and is configured to receive EUV radiation transmitted via the IU from a reflective pattern source and to initiate at the pattern source by using an EUV radiation beam that is incident on the pattern source Only two radiation beams, using a reduction factor N > 1 , form an optical image of the substantially 1D pattern of the pattern source on a plane that is optically conjugate to the pattern source. In general, the PO subsystem is configured to reduce the contrast of the optical image in a spatially frequency dependent manner.

Additional details and/or related specific examples of PO subsystems configured in accordance with the teachings of the present invention are disclosed in our prior application. In some embodiments, the PO subsystem is designed to operatively tolerate a certain level of optical aberrations. In other words, the PO subsystem can have residual optical aberrations, and if present, residual optical aberrations can include one or more of: field curvature of no more than 100 microns; spherical aberration of no more than 0.1 waves, hui Any of the aberrations and astigmatism; and no more than 20% distortion. In some embodiments, the PO subsystem includes a first reflector having a first radius of curvature and a second reflector including a second radius of curvature, the first radius of curvature and the second radius of curvature having Opposite sign. The PO subsystem can include a reflective system containing primary and secondary mirror systems, at least one of the primary and secondary mirror systems including two reflective elements that are spatially distinct from each other (eg, spatially disconnected) (eg, our prior application) This is described in detail in the U.S. Provisional Application Serial No. 62/487,245. A particular implementation of this PO subsystem will be apparent from the schematic diagrams of Figures 13A, 13B, in which elements of the IU (specifically, relay reflector 126) are shown and in which the primary reflector of the PO subsystem ( The auxiliary reflectors labeled M1) and the PO subsystem (labeled M2) each include Not only two reflective elements (M1-A, M1-B; and M2-A, M2-B) that are spatially distinct and spatially separated from one another. Considering the symmetry of the 1D pattern on the pattern source 144, 144', the gap between the two reflective elements of the reflector of the PO subsystem is preferably arranged along the direction of the 1D pattern (when the pattern is formed by a 1D diffraction grating) In the case of, for example, the gap or split between elements M1-A and M1-B is substantially parallel to the line of the 1D diffraction grating). In some embodiments, the constituent reflective elements of the PO subsystem reflector are symmetrical to each other about a plane containing the reference axis of the PO subsystem. In another embodiment, the reflective surface of at least one of the reflective elements from a pair of reflective elements forming a given reflector of the PO subsystem is defined as a surface that is rotationally symmetric about the reference axis of the PO subsystem. portion.

Optically constructed components

Although the components of the pupil construction are detailed in our prior application, some of the criteria and parameters specific to the particular implementation are discussed herein.

評估。 Examples of the parameters of the PO and IU presented above are illustrated in FIGS. 4A and 4B for the construction and related dimensions of the aperture of a specific example of the present invention. There is a 16.5 mm wide regular diamond field at the wafer (ie, a square field with a diagonal of 16.5 mm oriented at 45° to the X and Y axes) and assuming light from the source (114, 214-A; 214-B) The solid angle entered by the radiation is Ω = 0.03638 sr , which corresponds to the optical expansion of the IU. H _IU = ΩA _field =

Evaluation.

With further reference to Figures 1 and 2A, it will be appreciated that the specific example 100 (with details from 200) is suitably configured to provide optical elements 118 (FE1-A, FE1-B), 160 (blind field stop), 144 (Photomask) and the surface associated with wafer-stage 156A (eg, the surface of wafer 156 supported by the wafer stage) is an optical conjugate element as understood in the art. The reason is that one of the elements illuminated with light incident thereon is optically imaged to the point of the other of the elements via the optical system of the specific example 100. The specific example is configured to form an image of overlapping FE1-A and FE1-B at the mask element 144. The specific examples 100, 200 are also configured such that the source 114 (214-A, 214-B), the element 122 (FE2), and the (PO subsystem) aperture stop are optical conjugates. It should be appreciated that FIG. 1B is a schematic diagram and the divergence or convergence of a particular beam after it has been reflected or transmitted through a particular optical component of system 100 (the extent of which may vary depending on the particular detailed design of system 100) It may not be accurately represented in the schema. For the disclosure of additional details of the construction of the aperture, the reader is referred to the prior application of the present application (the disclosure of each of which is hereby incorporated by reference), and the disclosure of which is incorporated herein by reference in its entirety in its entirety in number.

General schematic diagram of a specific example of a 1D EUV system

Figure 5 schematically illustrates a specific example 500 of a 1D EUV system in which the relay mirror 126 has been removed and carries a grating pattern of the reticle 144' (in the reticle holder) as compared to the specific example 100 of Figure IB The surface of the substrate, not shown), has a non-zero curvature and therefore has a non-zero optical power. When the reticle 144' is configured for operation in reflection, the reticle 144' images the FE2 reflector 122 into the entrance pupil of the PO subsystem. After transmission from the source 114, the radiation beam 510 intersects the radiation beam diffracted by the reticle pattern toward the PO subsystem (as schematically illustrated by the dashed line EE) traversing very close to the reticle 144' (as shown) Or alternatively, the field stop 160' placed in close proximity to the wafer 156. The proximity distance of the split field stop 160' to the reticle (or wafer) is generally less than 3 mm, preferably less than 1 mm, more preferably less than 100 microns, and even more preferably less than 50 microns. .

Blind field diaphragm (pattern blind)

Referring to Figures 8A, 8B, and 8C, the blind field stop 160 of the system defines an optical aperture that is configured to determine the beam size to form a substantially polygonal shape of the exposure fields 810, 820, 830 (on the image surface 156). In a particular case, a diamond shape (shown as a diamond shape 810 in Figure 8A) or a hexagonal shape (820 of Figure 8B). The intended exposure field (and thus the exposure field to form an optical aperture) may be defined by a concave polygon (830 of Figure 8C). Thus, for example, the perimeter of aperture 160 of particular example 100 is generally defined by a polygon. This configuration addresses the practical problem of providing effective spatial overlap between directly adjacent exposure fields to create a uniform exposure area across the entire image surface/wafer 156. In particular, as understood by those of ordinary skill in the art, the polygonal shape facilitates efficient geometric stitching of images from subsequently formed exposure fields. For example, the example exposure field shown on substrate 156 in Figure 8A is oriented such that the diagonal of polygon exposure field 810 is parallel to the x-axis and y-axis of the system. While the aperture 160 is illustrated in FIG. 1B as being operational in transmission, it should be understood that in a related embodiment the pattern blind 160 can be configured to reflect light within the boundaries of the perimeter of the polygon of its optical aperture.

It will be appreciated that depending on the particular type/shape of the polygonal exposure field, more than two exposure passes across the image surface may be required to completely and thoroughly expose the image surface without leaving any non-exposure patches. To this end, one advantage of having an exposure field shaped according to the specific example 830 (which would require 6 passes to complete the exposure cycle) would be that this implementation would allow the overall system to be more resistant to field-dependent aberrations.

Additional details and/or specific examples are discussed in our prior application and are described in detail in U.S. Provisional Application Serial Nos. 62/352,545 and 62/353,245.

The size of the pattern blindness does not affect the exposure time and should be chosen to match the total optical spread of the illumination source. Wafer stage scanning speed and the width of the blind aperture of the pattern measured along the x-axis In inverse proportion. In some cases, a pattern blind aperture having a high aspect ratio shape (wide in X and very thin in Y) (e.g., having an aspect ratio of 5 to 1 or higher) may be preferred.

The optical output required for the light source that can be equipped with the 1D EUV system of the present invention is understandably dependent on the amount of radiant power necessary to properly expose the resist on the wafer and the economic yield.

EUV source and radiant power considerations

One example of a light source for use with the 1D EUV system of the present invention may be by a plasma based light source such as, for example, a laser driver (laser pumping) as described in US 8,242,695 and/or US 8,525,138 At least a portion of the plasma source is provided. The disclosure of each of these patent documents is incorporated herein by reference. If desired, the housing of the plasma source can be electrically grounded and/or reconfigured to change the total optical power delivered via the window of the source. As a heat source, this light source emits radiation in the UV spectral region, the visible spectral region, and the IR spectral region.

Although the total power of this source emitted in a solid angle of 4 π steradian may be estimated to be about 10 W based on power to pass the light source through its clear aperture, the applicable output from any source suitable for the particular example is only The output to the aperture of the illuminator 200 is delivered. It is worth noting that the radiant power output from the source required for proper operation of the total 1D EUV system also depends on the system's execution rate (for example, measured by the number of wafers (wph) processed in one hour) . An example of a graph representing the estimated required radiant power output in accordance with a change in execution rate in a 1D EUV system is established based on the following assumptions: a target execution rate of 100 wph; for a total dose of 30 mJ/cm 2 for wafers Double pass of each part; square exposure field (oriented at 45° with x and y axes, 16.5 mm along two diagonals, see 210 in Figure 2B); 5 seconds per wafer Additional burden time (primary wafer exchange and alignment measurements); a total of 5 seconds of acceleration time per wafer; 30 pulse minimums for each exposure zone; each with 50% at the reticle at 65% reflectance Six reflective surfaces with % diffraction efficiency; and an additional "geometry factor" due to the possible 50% loss of mismatch optical expansion between the illuminator and the PO. In other words, the "geometry factor" is the fraction of the source output power that is directed into the PO entrance pupil. The graph represents the power required at the illuminator inlet for a given execution rate, as well as the required pulse repetition rate and wafer stage acceleration. The portion of this figure is shown in Figure 6 for a particular value of the assumed parameter and for three different values for the geometric factor. Table 1 provides an additional summary of the results.

It will be appreciated that depending on the particular choice of light source used with a particular example of a 1D EUV system, the optical spread of this source may be less than the optical spread of the IU. In this case, the system can be configured for use with multiple light sources (eg, as shown in Figures 2A, 214-A and 214-B). The number of (additionally identical) light sources required in this case can be estimated as N _sources = H _IU / H _{single source} , where H _{single source} is the optical extension of a single source.

Additional details and/or specific examples of EUV radiation sources that are reasonably configured for operation in the 1D EUV system of the present invention are discussed in our prior application. For example, an example of a light collection schematic for this EUV source for use with an optical system of a 1D EUV exposure tool is shown in Figures 9A, 9B. 9A illustrates a laser driver having an ellipsoidal mirror for refocusing EUV radiation from LPP to IF, which in turn acts as a light source for a specific example of the IU of the present invention. Configuration of the plasma source. The 5sr collector and 1.6sr subaperture configuration are shown schematically for comparison. 9B is a schematic diagram of a ray model based on the laser driven plasma source of FIG. 9A illustrating a collector 910 having a central opening 910A, a tin ejector 214, and an auxiliary source IF 916.

The specific model of the EUV source of Figures 9A, 9B includes an aperture that sets the boundary of the Gaussian irradiance distribution of light proportional to the distance from the IF 916 and an obscuration mask (formed by a combination of two circles and rectangles) .

The model further includes the following effects: i) three-dimensional (3D) distribution of plasma emission 918; (ii) elliptical mirror difference, obscuration and reflectance variation; (iii) obscuration caused by tin ejector 214. The model of the source is further assumed to have: a) a 650 mm diameter ellipsoidal collector; b) a source having an NA defined by a 5sr solid angle; c) having a 90 micron diameter at the FWHM (or at a 1/e2 level) Approximately 910 micrometers of approximately Gaussian projection of the plasma 918 radiation distribution. The results of the simulated projection of this distribution with FRED® are presented in Figures 9C, 9D; d) IF 916 with a NA of 0.25; e) 20% central disc shaped obscuration 910A (approximately 130 mm diameter); and f) 15% linear obscuration (100 mm width) caused by tin ejector 914. The reflectivity of collector 910 is assumed to be about 50%, and the effective diameter of IF 916 (considering the instability of the laser driven plasma source) is assumed to be about 2 mm. The modeled spatial distribution of light produced by the plasma source and the modeled spatial distribution at the plane of the IF 916 can be self-explanatory of the intensity distribution of Figures 10A, 10B, and the ray points at the plane of the IF 916 shown in Figure 11A. Schematic and graphical evaluation of the ray direction at the same plane as shown in Figure 11B.

Considerations for lithography processes using specific examples of the invention

When the mask (mask) 144 used in the specific example of the 1D EUV system of the present invention is configured as a phase shift mask (PSM) to increase the contrast of an image formed at the substrate, The resulting features of the printed image are improved compared to their features implemented using conventional 2D EUV systems.

The simulation of the proposed 1D EUV system was performed under the imaging simulation conditions outlined in Table 2. For comparison, the relevant parameters of the prior art 2D EUV system are also listed.

Table 3 shows the area image contrast of a 1D raster printed at 0.33NA and 0.55NA using the specific example of the proposed 1D EUV tool and the prior art standard 2D EUV tool. The 0.33NA tool is completely unprintable with a 20 nm pitch grating and produces lower contrast using imaging with a 0.55 NA tool. For comparison, FIG. 7A shows data output from a resist model at a preferred dose for focusing on a standard high NA 2D EUV tool of a specific example of the present invention and prior art.

Figures 7B, 7C additionally illustrate the exposure dose (in millijoules / for the 2D EUV system with a NA of 0.55 and with a binary mask, and for the specific example of the invention (NA = 0.4, PSM) discussed above, respectively. Printed in square centimeters) and defocused (in microns) The dependence of the critical dimension (CD) of the pattern on the substrate. While a particular embodiment of the invention may require a higher dose of radiation, the specific example indicates a substantially smaller reduction in image quality: relatively speaking, the deterioration of a given value of CD in a 1D EUV system is substantially less than Deterioration in 2D EUV systems. For example, as seen from the comparison of curves A and B of Figures 7B and 7C, defocusing of about 0.05 microns causes an increase in the CD of the 2D EUV system from about 11 nm to about 14.5 nm, and the 1D EUV system. It is only an increase from about 12.5 nm to about 13.5 nm. Those skilled in the art will readily appreciate the advantages of increased contrast achieved by the use of specific examples of the present invention.

The concept of a 1D EUV exposure tool has been outlined in accordance with an example of a specific example described with reference to Figures 1-11. Although specific values selected for this particular example are recited, it should be understood that within the scope of the present invention, the values of all parameters can be varied over a wide range to suit different applications. For example, specific examples of the invention have been described as not telecentric at the plane of the reticle and having a reticle position that is fixed during exposure. However, between exposure execution, or during exposure, the reticle can be slightly moved along the z-axis (if necessary) to induce a change in the magnification of the image and effectively allow the exposure tool of the present invention to expand/contract the imaged 1D pattern. Used to geometrically match the pattern that has been printed on the substrate.

Specific examples have been described as including control circuitry/processors that are controlled by instructions stored in memory. The memory can be random access memory (RAM), read only memory (ROM), flash memory or any other memory suitable for storing control software or other instructions and data, or a combination thereof. Those skilled in the art should also readily appreciate that the instructions or programs defining the functionality of the present invention can be in many forms (including but not limited to being permanently stored on a non-writable storage medium (eg, a read-only memory device (such as a ROM) within a computer). , or information stored on a readable device (such as a CD-ROM or DVD disc) by computer I/O, variably stored in a writable storage medium (eg Information on a flexible disk, removable flash memory, and hard disk drive, or information transmitted to a computer via a communication medium (including a wired or wireless computer network) is delivered to the processor. In addition, although the present invention may be embodied in a software, the functions necessary for implementing the present invention may alternatively or alternatively use firmware and/or hardware components (such as combinatorial logic, special application integrated circuits (ASIC), field programmable Partial or integral representation of a gated array (FPGA) or other combination of hardware or hardware, software and/or firmware components.

Table 4 summarizes the advantageous operating parameters of one particular embodiment of the present invention compared to the operating parameters of some 2D EUV systems.

Based on the combination of the present disclosure and the disclosure of our prior application, those skilled in the art will readily appreciate various specific examples of 1D EUV systems that have been discussed for printing arrays of straight parallel lines on selected workpieces. Specific examples include, but are not limited to:

- A specific example of an (EUV) exposure tool comprising: an IU; a reflector (containing a pattern source on which a substantially 1D pattern is carried; the reflector is positioned to receive an incident beam of EUV radiation from the IU); A system having a reference axis and configured to receive radiation from an incident beam transmitted from the reflector. In one embodiment, the reflector includes a phase shifting mask. The PO subsystem is also configured to employ a reduction factor N > 1 and form a 1D pattern on the plane optically conjugated to the reflector by using only two of the radiation beams originating from the incident beam at the reflector. Optical image. The substantially 1D pattern has a first spatial frequency and its optical image has a second spatial frequency, and the second spatial frequency is at least twice the first spatial frequency. The reflector is placed in a substantially fixed spatial and optical relationship with respect to the IU and PO subsystems. Only two of the radiation beams forming the optical image do not include a radiation beam representing the specular reflection of the incident beam at the reflector. The exposure tool can further include a workpiece configured to be movable transverse to the reference axis. In certain instances, the IU includes first and second fly's eye (FE) reflectors. Additionally or in the alternative, the reflector may be disposed between the individual constituent reflective elements of the first FE reflector. In general, the PO subsystem includes first and second reflectors (the first reflector has a first radius of curvature, the second reflector includes a second radius of curvature, and the first and second radii of curvature have opposite signs). In one implementation, the PO subsystem is a reflective system containing primary and secondary mirror systems, and at least one of the primary and secondary mirror systems includes two reflective elements that are spatially distinct from one another.

- A specific example of a 1D EUV exposure tool comprising: an IU (having first and second fly's eye reflectors as constituent reflectors of the IU); a PO subsystem in communication with the IU light; a reflective pattern source, Positioning and carrying a substantially 1D pattern thereon with respect to substantially fixed spatial and optical relationships of the IU and PO subsystems (the pattern source is configured to receive a radiation beam from the IU and transmit radiation from the radiation beam to PO subsystem); and can be relative to PO The workpiece whose reference axis moves laterally. The IU may further include a relay mirror disposed in optical communication with both the second fly's eye reflector and the reflective pattern source. In one particular implementation, the 1D EUV exposure tool additionally includes a field stop disposed between the second fly's eye reflector and the relay mirror. The field diaphragm generally defines an optical aperture having a polygonal perimeter. Additionally or in the alternative, the 1D EUV exposure tool is configured such that the first fly's eye reflector, the field stop, the pattern source, and the surface associated with the workpiece are optically conjugate to each other. In general, the PO subsystem includes a first mirror and a second mirror, at least one of which has a central obscuration. The first and second mirrors are configured to collectively define an astigmatic optical system. In certain cases, the PO subsystem further includes a third mirror. In a particular implementation, the PO subsystem has only two reflectors. In a related implementation, the PO subsystem has only three reflectors. The exposure tool can be configured such that EUV radiation from the radiation beam is passed through the IU by using no more than ten reflectors (where the ten reflectors include the first and second fly's eye reflectors and the reflector of the PO subsystem) And the PO subsystem is delivered toward the workpiece along the reference axis. The pattern source of the tool is generally equipped with a pattern source support that does not contain a structure that is configured to scan the pattern source in a manner that is synchronized with the motion of the workpiece during operation of the exposure tool. In a particular implementation, the surface of the pattern source carrying the 1D pattern can have a non-zero radius of curvature to define the non-zero optical power of the pattern source. In this case, the surface of the pattern source has a first finite radius of curvature defined in the first plane, the first plane being transverse to the surface and containing a pattern source axis perpendicular to the surface. Additionally, the surface of the pattern source can have a second finite radius of curvature defined in the second plane, the second plane being transverse to the first plane and containing the axis of the pattern source. The first and second finite radii of curvature may be substantially equal to each other. The 1D EUV exposure tool can additionally include a radiation source configured to emit radiation at the EUV wavelength and positioned to optically conjugate with the second fly's eye reflector and the entrance pupil of the PO subsystem. In one case, the radiation source contains a plasma driven light emitter. 1D EUV exposure tool can be further equipped with a control unit The control unit has a processor that is programmed to perform the following operations: (i) along the first axis (the radiation delivered by the PO subsystem using the self-reflective pattern source is relatively close to a position of the exposure field formed in a plane of the surface of the workpiece) and a strip along the first scan trajectory to form a parallel line extending along the first axis; and (ii) when a pre-existing pattern is discussed The first scan trajectory is adjusted to correlate the strips to a portion of the pre-existing pattern when the scan is associated with the workpiece. In certain instances, the processor is programmed to adjust the first scan trajectory during the process of scanning the workpiece, including at least one of (a) moving along the second axis and (ii) moving along the third axis, second The axis is perpendicular to the first axis and the third axis is perpendicular to both the first axis and the second axis. The control unit can be further operatively cooperated with at least one of the IU and PO subsystems, and the processor can be further programmed to adjust the spacing of the strips of the parallel lines to deform the strip.

- A specific example of a method for transmitting radiation via a 1D EUV exposure tool. The method includes the step of transmitting a first EUV radiation (received by a first reflector of the IU of the EUV exposure tool) to a reflective pattern source of the 1D EUV exposure tool, the pattern source being substantially fixed in space relative to the first reflector of the IU In the relationship. The method includes a second step of transferring the first EUV radiation (which has interacted with the reflective pattern source) further through the surface of the reflective surface containing the first mirror. For example, the transmitting can include transmitting the first EUV radiation through the central aperture or center of the first mirror. In one case, transmitting the first EUV radiation through the central obscuration can include transmitting the first EUV radiation through the central aperture, the surface area of the central aperture not exceeding 40% of the area of the reflective surface of the first mirror. The act of transmitting may include the first beam of the first EUV radiation colliding to a first location at the surface of the first mirror and the second beam of the first EUV radiation colliding to a second location at the surface of the same first mirror The first position and the second position are defined on opposite sides of the first mirror relative to the reference axis On the surface. Alternatively or additionally, the method further comprises (a) reflecting the first radiation from a surface on which the substantially one-dimensional (1D) pattern of the pattern source is carried and/or (b) further comprising using a reduction factor of N > 1 An optical image of a substantially 1D pattern is formed on the target surface optically conjugate with the reflective pattern source. The step of forming an optical image includes forming an optical image using only two radiation beams initiated at the source of the reflective pattern due to the transfer step, and the only two of the radiation beams are not including the first EUV radiation at the source of the reflective pattern Specularly reflected beam. The method can additionally include the step of forming an optical image wherein the separation distance between two directly adjacent linear elements of the image does not exceed 10 nanometers; and preferably does not exceed 7 nanometers. In one implementation, the method further includes the step of varying the curvature of the wavefront of the first EUV radiation after the radiation interacts with the reflective pattern source. The method can further include (i) transmitting the first EUV radiation through the second mirror and partially reflecting the first radiation at a surface of the second mirror opposite the optical axis of the second mirror. In this case, the step of further transmitting and transmitting the first radiation through the second mirror collectively defines the transmitted radiation through an astigmatism mirror system having a numerical aperture of at least 0.2.

The use of the terms "substantially", "substantially", "about" and similar terms with respect to values, elements, properties or characteristics is intended to emphasize the reference to the disclosure and the scope of the appended claims. The value, component, nature, or characteristics of the invention, although not necessarily stated in its entirety, will still be considered as a These terms (such as applied to a specified characteristic or quality descriptor) mean "majority", "mainly", "significantly", "substantially", "substantially", "to a large extent", " Substantially, but not necessarily identical, in order to properly represent the approximation language and describe the specified feature or descriptor such that its scope will be understood by those skilled in the art. In a specific case, the terms "substantially", "substantially" and "about" when used in reference numbers indicate a range of plus or minus 20% relative to the specified value, preferably positive or negative. 10%, even better positive or negative 5%, the best is positive or negative 2% relative to the specified value. By way of non-limiting example, two values that are "substantially equal" to each other means that the difference between the two values can be within the range of +/- 20% of the value itself, preferably +/- 10% of the value itself. Within the range, it is more preferably within the range of +/- 5% of the value itself, and even more preferably within the range of +/- 2% or less of the value itself.

The use of such terms in describing a selected characteristic or concept does not mean or provide any basis for the limitation and the addition of a numerical limitation to a specified characteristic or descriptor. As will be understood by those skilled in the art, when using the measurement methods accepted in the art for such purposes, the actual deviation of the exact value or the characteristics of the value, component or property from the statement is typical. The range of values defined by the experimental measurement error can vary within the range of values defined by typical experimental measurement errors.

For example, a reference to an identified vector or line or plane substantially parallel to a reference line or plane will be considered to be the same or very close to the reference line or plane of the vector or line or plane of the referenced line or plane ( The angular deviation from the reference line or plane is considered to be a typical value in the prior art, for example between zero and fifteen degrees, preferably between zero and ten degrees, more preferably between zero and five. Between degrees, even better between zero and 2 degrees, and optimally between zero and one degree). For example, a reference to an identified vector or line or plane that is substantially perpendicular to a reference line or plane will be considered as a vector or line whose normal to the surface is at the reference line or plane or very close to the reference line or plane or Plane (where the angular deviation from the reference line or plane is considered to be a typical value in the prior art, for example between zero and fifteen degrees, preferably between zero and ten degrees, more preferably zero degrees Between 5 degrees, even better between zero and 2 degrees, and optimally between zero and 1 degree). The term "substantially rigid" is generally used when used with respect to a housing or structural element that provides mechanical support for the new invention in question. A structural element having a hardness higher than that of the newly invented support of the structural member. As another example, the use of the term "substantially flat" with respect to a specified surface means that the surface can have a size that is set in a particular situation that is about to come and is expressed as an unevenness that is generally understood by those skilled in the art and/or Or the degree of roughness.

Other specific examples of the meanings of the terms "substantially", "about" and/or "substantially" as used in the context of the practice may be provided elsewhere in the present invention.

Specific examples of the system of the present invention include electronic circuitry (e.g., a computer processor) that is controlled by instructions stored in memory to perform the particular data collection/processing and calculation steps as disclosed above. The memory can be random access memory (RAM), read only memory (ROM), flash memory or any other memory suitable for storing control software or other instructions and data, or a combination thereof. Those skilled in the art should readily appreciate that the instructions or programs defining the operations of the present invention can be stored in many forms including, but not limited to, permanently stored on a non-writable storage medium (eg, a read-only memory device (such as a ROM) within a computer). , or information stored on a readable device (such as a CD-ROM or DVD disc) by computer I/O, variably stored in a writable storage medium (eg, a flexible disk, removable flash) Information on the memory and hard drive, or information transmitted to the computer via a communication medium (including a wired or wireless computer network) is delivered to the processor. In addition, although the present invention may be embodied in a software, the functions necessary for implementing the present invention may alternatively or alternatively use firmware and/or hardware components (such as combinatorial logic, special application integrated circuits (ASIC), field programmable Partial or integral representation of a gated array (FPGA) or other combination of hardware or hardware, software and/or firmware components.

The invention as described in the claims of the present disclosure is intended to be evaluated as a whole in accordance with the disclosure. Each of the details, steps, and components that have been described Variations can be made by those skilled in the art within the principles and scope of the invention.

For example, referring to Fig. 12, a schematic diagram illustrating a portion of an optical system (of the 1D EUV exposure tool of the present invention) that is slightly modified compared to the specific example of Fig. 5 is shown. (Note that for simplicity of illustration, this schematic of Figure 12 is presented without regard to the accuracy of the scale, shape or mutual orientation and/or the positioning of the depicted components). Here, as in the specific example 500 of FIG. 5, a pattern source 144' carrying a substantially 1D pattern that is optically imaged onto the image surface typically associated with the workpiece 156 via the PO subsystems 134, 130 is carried. The surface is curved in space. However, compared to the specific example 500, the pattern source 144' utilizes EUV radiation (shown as arrow 1210) that arrives from the auxiliary source 916 of light IF (as discussed above, due to the operation of the EUV source of the system). It is referred to as an off-axis oriented directional illumination. In particular, the general direction of the propagation 1210 incident on the pattern source EUV radiation forms a tilted non-zero incident angle with respect to the normal 1220 that defines an axis that is perpendicular to the surface of the curved pattern source 144'. In certain instances, the angle of incidence of EUV radiation 1210 onto pattern source 144' is selected to ensure that, for example, the average wave vector of radiation 1210 onto the surface of pattern source 144' is substantially parallel to the substantially 1D pattern. The axis along which the line extends. For example, where the substantially 1D pattern of the pattern source is formed by a 1D diffraction grating, the plane of incidence of the radiation 1210 onto the pattern source 144' is substantially parallel to the grating line and the reference axis (such as normal 1220) ). As shown in the view of FIG. 12, the substantially 1D patterned line of pattern source 144' extends along the y-axis.

Referring again to FIG. 1B, for example, a similar configuration of off-axis illumination of a pattern source can be employed in an optical system (of a 1D EUV exposure tool) employing a substantially planar or flat pattern source 144, and/or in use. It is employed in the optical system of the reflector 126. It should also be understood that off-axis illumination of the source of the pattern (as described above, whether flat or curved) can generally be used to different The collimation is characterized by an EUB radiation beam. For example, off-axis illumination of the pattern source can utilize a substantially collimated EUV radiation beam configuration that arrives from the IU; in another non-limiting example, this EUV radiation beam can spatially converge toward the pattern source.

Accordingly, the scope of the present invention includes this mutual orientation of the IU and the pattern source within the optical system of the 1D EUV exposure tool, and the final optical element of the IU (which is an FE reflector or a relay reflector) uses the optical of the 1D EUV exposure tool. The system reflects EUV radiation along the axis toward the pattern source, the projection of the axis onto the pattern carrying surface of the pattern source being parallel to the longitudinal extent of the elements of the substantially 1D pattern.

The choice of off-axis illumination configuration may be beneficial to reduce the loss of imaging contrast across the FOV, and in some cases may be beneficial to reduce or avoid phase effects that may otherwise be compensated for by changing the structure of the light source or the structure of the pattern source itself. (The effect of radiation from the pattern source through the PO subsystem and further propagation toward the image surface). Consider the fact that, in general, acceptable variations in at least the structure of the pattern source used with the specific examples of the present invention are limited, and the implementation of off-axis illumination of the pattern source may prove to be practically advantageous. Due to the substantially 1D nature of the pattern of pattern sources 144, 144' and the system is configured to ensure that the optical components do not interfere with the propagation of +1 and -1 order diffraction through the PO subsystem (as in our previous application) The fact that the zero-order diffraction formed at the source of the pattern from the incident radiation 1210 is substantially blocked at the same time as discussed herein is somewhat less stringent for a particular angle of incidence in a particular embodiment of the invention. Referring to Figure 12, by way of example, in one embodiment, the angle of radiation arriving from the IU on the pattern source is in the range of from about zero to about 40 degrees; in a related embodiment, from about 10 degrees to about Within 30 degrees. It should be understood that these ranges merely provide examples of angular ranges. In practical embodiments, the angle or range of angles of incidence from 0 to substantially 90 degrees can be used anywhere.

The disclosed aspects, or portions of such aspects, may be combined in ways not listed above. Therefore, the invention should not be considered as limited to the specific examples disclosed.

114‧‧‧Light source

118‧‧‧First reflector

122‧‧‧second reflector

126‧‧‧Relay reflector

130‧‧‧ first mirror

130A‧‧‧Center Coverage

134‧‧‧second mirror

134A‧‧‧ center cover

140‧‧‧ radiation

144‧‧‧ pattern source

148‧‧‧radiation

152A‧‧‧beam

152B‧‧‧beam

156‧‧‧ wafer

156A‧‧‧ wafer stage

160‧‧‧ aperture

164‧‧‧Photonics/Aperture

Claims (47)

An extremely short ultraviolet (EUV) lithography engraving machine configured to print a one-dimensional (1D) line on a target workpiece, the reticle comprising: a very short ultraviolet source configured to emit very short Ultraviolet radiation; a holder configured to hold a pattern source defining a substantially one-dimensional pattern in a substantially fixed position; a workpiece stage configured to be held relative to the holder held by the holder A pattern source moves the target workpiece; a lighting unit (IU) configured to illuminate the pattern source with the very short ultraviolet radiation; a projection optics (PO) subsystem at the illumination unit and the workpiece carrier Between the stages, the projection optics subsystem is configured to form an optical image of the one-dimensional pattern in the image surface when the target workpiece is repositioned by the workpiece stage, the image surface being the target workpiece surface. A scriber of claim 1, wherein the image surface is optically conjugated to the substantially one-dimensional pattern. The scriber of claim 1, wherein the workpiece stage is configured to be at a substantially constant speed when the target workpiece is exposed to the extremely short ultraviolet radiation via the projection optics subsystem The target workpiece is moved during the scanning motion of the feature. The scriber of claim 1, wherein the illumination unit comprises: a first fly's eye (FE) reflector positioned to collect the radiation from the extremely short ultraviolet light source; and a second fly's eye reflector, Causing to receive the radiation from the first fly's eye reflector; wherein the illumination unit and the pattern source optically cooperate to form a projection optics An illumination pupil of the subsystem, the illumination pupil being defined by the intersection of two plan views, and wherein the scorer is configured to transmit at least a portion of the very short ultraviolet radiation within the boundary of the illumination pupil. A scriber as claimed in claim 4, wherein the illumination pupil is defined by the intersection of two circles. A reticle as claimed in claim 4, which is configured to transmit substantially all of said very short ultraviolet radiation within said boundaries. A reticle as claimed in claim 4, wherein the illumination unit further comprises: a relay reflector configured to reflect the radiation toward the pattern source, the radiation having been reflected by the second fly's eye reflector. The scriber of claim 1, wherein the projection optics subsystem comprises a first reflector and a second reflector, wherein at least one of the first and the second reflector comprises two in space Upper reflective elements. A reticle as claimed in claim 8 wherein the projection optics subsystem comprises a third reflector. The scriber of claim 1, wherein the projection optics subsystem is characterized by optical aberrations, if the optical aberrations are present, including one or more of the following: an image of no more than 100 microns Field curvature; any of spherical aberration, coma aberration and astigmatism of no more than 0.1 wave; and no more than 20% distortion. A reticle as claimed in claim 1, wherein the pattern source comprises a phase diffraction grating configured to form a beam of diffraction order indicative of the very short ultraviolet radiation, the diffracted The order includes +1 and -1 order diffraction. The scriber of claim 11, wherein the projection optics subsystem comprises a plurality of reflectors, each reflector from the plurality of reflectors being disposed to reflect the +1 and -1 order windings At least one of the shots. A reticle as claimed in claim 1, wherein the pattern source comprises any one of the following: a reflective diffraction grating; an amplitude diffraction grating; and a transmission diffraction grating. The scriber of claim 1, wherein the surface of the pattern source carrying the substantially one-dimensional pattern is curved or flat. An extremely short ultraviolet (EUV) lithography engraving machine configured to print a one-dimensional (1D) line on a target workpiece, the reticle comprising: a very short ultraviolet source configured to emit very short Ultraviolet radiation; a pattern source carrying a substantially one-dimensional pattern; an illumination unit (IU) configured to illuminate the pattern source with the extremely short ultraviolet radiation; and a projection optics (PO) subsystem, An optical image of the one-dimensional pattern is formed on the image surface as the image surface is being moved relative to the pattern source, wherein the projection optics subsystem includes first and second reflectors, the At least one of the first and second reflectors includes first and second spatially distinct reflective elements. A scriber of claim 15, wherein the at least one of the first and second reflectors is symmetrical with respect to an axis or with respect to a plane. A reticle as claimed in claim 15 wherein at least one of the first and second reflective elements defines a portion of the rotatable surface. The scriber of claim 15, wherein the projection optics subsystem is characterized by optical aberrations, if any, including one or more of the following: an image of no more than 100 microns Field curvature; any of spherical aberration, coma aberration and astigmatism of no more than 0.1 wave; and no more than 20% distortion. A reticle as claimed in claim 15 wherein the first and second reflectors then collectively define an astigmatic optical system. A scriber of claim 15 further comprising: a holder configured to hold the pattern source in a substantially fixed position; and a workpiece stage configured to be at the pole When the short ultraviolet radiation is delivered to the image surface, the target workpiece defining the image surface is repositioned relative to the pattern source held by the holder. The scriber of claim 15 further comprising: a first fly's eye (FE) reflector positioned to collect the extremely short ultraviolet radiation from the very short ultraviolet light source; the second fly eye reflex The device is positioned to receive the very short ultraviolet radiation from the first fly's eye reflector; wherein the illumination unit and the pattern source are operatively cooperated to form an imaging stop for the projection optics subsystem The imaging pupil is defined by the intersection of two plan views, and wherein the reticle is configured to transmit the very short ultraviolet radiation within the boundary of the imaging pupil At least part of it. The scriber of claim 21, further comprising: a relay reflector configured to reflect the extremely short ultraviolet radiation toward the pattern source, the extremely short ultraviolet radiation having been subjected to the second Fly eye reflector reflection. A reticle as claimed in claim 21, wherein the imaging pupil is defined by the intersection of two circles and wherein the reticle is configured to transmit substantially all of the ultra-short ultraviolet light within the boundaries radiation. An extremely short ultraviolet (EUV) lithography engraving machine configured to print a one-dimensional (1D) line on a target workpiece, the reticle comprising: a very short ultraviolet source configured to emit very short Ultraviolet radiation; a pattern source carrying a substantially one-dimensional pattern; an illumination unit (IU) configured to illuminate the pattern source with the extremely short ultraviolet radiation; and a projection optics (PO) subsystem, Between the illumination unit and the workpiece stage, the projection optics subsystem is configured to form an optical image of the one-dimensional pattern on the image surface using a reduction factor N>1, the image surface and the essence The upper one-dimensional pattern is optically conjugated, wherein the one-dimensional pattern has a first spatial frequency, the optical image has a second spatial frequency, and the second spatial frequency is at least twice the first spatial frequency. A reticle as claimed in claim 24, wherein the projection optics subsystem is configured to apply only at the source of the pattern in response to applying the very short ultraviolet radiation to illuminate the pattern source via the illumination unit Two beams form the image. Such as the marking machine of claim 24, which is configured to not allow on the surface of the image An image of a two-dimensional pattern is formed in one exposure. A reticle as claimed in claim 26, which is configured to not permit formation of the image of the two-dimensional pattern, wherein the two-dimensional pattern has a spatial resolution substantially equal to the pitch of the substantially one-dimensional pattern. A reticle as claimed in claim 24, wherein the illumination unit and the pattern source operatively cooperate to form an imaging pupil for the projection optics subsystem, the imaging pupil being intersected by two plan views Point defining, and wherein the reticle is configured to transmit at least a portion of the very short ultraviolet radiation within a boundary of the imaging pupil. The scriber of claim 24, wherein the illumination unit comprises: a first reflector positioned to receive the extremely short ultraviolet radiation from the extremely short ultraviolet light source; and a second reflector State to obtain the extremely short ultraviolet radiation reflected by the first reflector; and a relay reflector configured to reflect the very short ultraviolet radiation toward the pattern source, the extremely short ultraviolet radiation having been The second reflector reflects. A reticle as claimed in claim 24, wherein the illuminating unit comprises only two reflectors. A scriber of claim 30, wherein at least one of the only two reflectors is a fly's eye (FE) reflector. A reticle as claimed in claim 29, wherein each of the first reflector and the second reflector is a fly's eye (FE) reflector. A scriber of claim 24, further comprising: a holder configured to hold the pattern source in a substantially fixed position; and a workpiece stage configured to lend relative to The pattern source held by the holder moves the target workpiece, the surface of the target workpiece defining the image surface. A scriber of claim 24, wherein the pattern source comprises a one-dimensional phase diffraction grating. A reticle as claimed in claim 24, which is configured to form the optical image using only two beams that have traversed the projection optics subsystem, the only two beams representing the response being extremely short Ultraviolet radiation illuminates the pattern source and +1 and -1 order diffraction formed by the one-dimensional pattern. A reticle as claimed in claim 24, wherein the pattern source comprises any one of: a reflective diffraction grating; a transmission diffraction grating; and an amplitude diffraction grating. A reticle as claimed in claim 24, wherein the pattern source comprises any one of: a reticle patterned with only one dimensional lines; and an array of reflectors defined by only one dimensional lines. The scriber of claim 24, wherein the surface of the pattern source carrying the substantially one-dimensional pattern is curved or flat. A reticle as claimed in claim 24, wherein the projection optics subsystem comprises a first reflector and a second reflector. A scriber of claim 24, wherein the projection optics subsystem comprises only There are only two reflectors, at least one of which only includes first and second reflective elements that are spatially distinct from one another. A reticle as claimed in claim 24, further comprising a light blocking member disposed to block the propagation of the zero-order diffracted beam toward the image surface, the zero-order diffracted beam being responsive to the application of the extremely short ultraviolet radiation The pattern source is illuminated to form at the source of the pattern. A reticle as claimed in claim 24, wherein the projection optics subsystem comprises first, second and third reflectors. The scriber of claim 24, wherein the projection optics subsystem is characterized by optical aberrations, if any, including one or more of the following: an image of no more than 100 microns Field curvature; any of spherical aberration, coma aberration and astigmatism of no more than 0.1 wave; and no more than 20% distortion. The scriber of claim 24, wherein the illumination unit is configured to illuminate in an incident plane parallel to (i) an extension direction of the one-dimensional pattern and (ii) a normal to a surface of the pattern source The source of the pattern. The scriber of claim 24, wherein the one-dimensional pattern forms a one-dimensional diffraction grating, and wherein the illumination unit is configured to illuminate the pattern source along a first axis, the first axis to the pattern The projection on the surface of the source is parallel to the line of the grating. A reticle as claimed in claim 45, wherein the average wave vector of the extremely short ultraviolet radiation incident on the pattern source from the illumination unit is substantially parallel to the first axis. A reticle as claimed in claim 24, wherein the illumination unit is configured to illuminate the pattern source substantially perpendicular to a surface of the pattern source.