TW201235796A - Methods, systems and apparatus for monitoring integrity of an article, EUV optical apparatus incorporating the same - Google Patents

Abstract

Methods, systems and apparatus are described for monitoring integrity and/or a contamination particle of an article, which may be, for example, a spectral purity filter in an EUV lithographic apparatus. To monitor integrity of an article operating in a low pressure environment, a beam of electrons is directed toward the article within the environment. The article when intact is configured to stop at least a proportion of the electrons in the beam, and a signal is generated to indicate integrity status of the article by identifying when at least a part of the article is not stopping the expected proportion of electrons in the beam. The electrons can be detected in the article itself, or in a screen or other detection device behind the article. EUV optical apparatus incorporating the methods, systems and apparatus are also described.

Description

201235796 VI. Description of the Invention: [Technical Field of the Invention] The present invention relates to a method, system and apparatus for monitoring the integrity of an article operating in a low pressure or vacuum environment. An example of an item to be monitored may be a spectral purity filter in an extreme ultraviolet (lin) optical system such as a lithography apparatus. [Prior Art] A lithography apparatus is a machine that applies a desired pattern onto a substrate (usually applied to a target portion of the substrate). The lithography device can be used in the manufacture of, for example, an integrated circuit (ic). In this case, a patterned device (which may be referred to as a reticle or a proportional reticle) can be used to create a circuit pattern to be formed on individual layers of the IC. This pattern can be transferred to a target portion (eg, 'including a portion of a die, a die, or several grains) on a 锊丨芏丞", 锊丨芏丞 plate (eg, 矽 wafer). Usually via imaging Transferring the pattern to a layer of light-sensitive material (anti-synthesis agent) provided on the substrate. Typically, the single-substrate will contain a network of sequentially adjacent adjacent target portions. The shadow device includes: a stepper, wherein each of the target portions is turned by exposing the entire pattern to the target portion at a time; and a scanner, wherein the radiation beam is transmitted in a given direction ("scanning" direction) While the scanning pattern is simultaneously parallel or anti-parallel in this direction, the substrate is scanned synchronously to lightly photograph each of the target portions. It is also possible to transfer the pattern from the patterned device to the substrate by imprinting the pattern onto the substrate. The key factor limiting the pattern printing is the wavelength λ of the radiation used. In order to be able to project smaller and smaller structures onto the substrate, it has been proposed to use very violet 160397.doc

S 201235796 External line (EUV) Koda Shot, which is electromagnetic radiation having a wavelength in the range of j 〇 nanometer to 2 〇 nanometer (for example, in the range of 13 nm to 14 nm). It has further been proposed to use Euv radiation having a wavelength of less than 1 nanometer (e.g., in the range of 5 nanometers to (7) nanometers (e.g., 6.7 nanometers or 6.8 nanometers). This EUV radiation is sometimes referred to as soft ray radiation. Possible sources include, for example, laser-generated plasma sources, discharge plasma sources, or synchrotron light from electronic storage rings. The Sn-based EUV source not only emits rEUV radiation, but also emits out-of-band radiation, most notably in the deep UV (DUV) range (1 〇〇 to 400 nm). In addition, in the case of laser-generated plasma (Lpp) Euv sources, infrared radiation from the laser (typically at 1 〇 6 microns) exhibits a large amount of unwanted radiation. Because the optics of an EUV lithography system typically have substantial reflectivity at these wavelengths, unwanted radiation can propagate to the lithography tool with significant power if no measures are taken. In lithography devices, out-of-band radiation should be minimized for several reasons. First, the resist is sensitive to out-of-band wavelengths and, therefore, may degrade image quality. Second, unwanted radiation (especially radiation of 1 〇 6 microns in LPP sources) can result in unwanted heating of the reticle, wafer, and optics. Currently, spectral purity filters (SPF) can be implemented to place unwanted radiation within specified limits. The SPF can be of the transmissive type or the reflective type. Transmission Type SPF can be formed by a planar article such as a thin diaphragm or grid of micro-sized pores. However, SPF failure or leakage can occur during operation, which causes some or all of its loss of ability to remove out-of-band radiation, and thus can impair imaging performance and/or damage the machine. Therefore, the spF fault detection I60397.doc ^ 201235796 method is needed to monitor the SPF to prevent the formation of holes. Ideally, the monitoring system should function outside of the beam itself. BRIEF DESCRIPTION OF THE DRAWINGS [0009] A simplified summary of one or more embodiments is presented below to provide a basic understanding of the embodiments. This Summary is not an extensive overview of the various embodiments, and is not intended to identify key or critical elements of the embodiments. The sole purpose is to present some embodiments of the embodiments in the In accordance with one or more embodiments, methods, systems, and apparatus are provided for monitoring the integrity of an item. In accordance with an embodiment of the present invention, a method for monitoring the integrity of an item operating in a low pressure environment is provided. The method includes directing an electron beam toward the article within the environment, the form of the article being expected to block at least a proportion of the electrons in the beam when intact; and based at least in part on receiving the electron beam The ratio of the electrons of the beam blocked by the item produces a signal indicative of the integrity status of the item. For example, an alert signal may be generated when at least a portion of the article does not block an expected ratio of one of the electrons in the beam. In the case of the "proportion" of the electrons that are "expected" to be blocked, the ratio can be determined in different ways and can be expressed in different ways in the design of the device, which is familiar to those skilled in the art. understanding. These terms are only used to indicate that an integrity test is based on the proportion of electrons that are blocked to distinguish between a complete item or part of an item and an incomplete item or article. Partially, and without any meaning greater than that. The test does not need to be based on the calculation of the ratio so expressed, but can be based on a single measurement that can be inferred to be blocked. Soil - A system for monitoring the integrity of an item in a low pressure environment is provided in accordance with the present invention. The system includes: an electron beam source module configured to direct the electron beam toward the object in the environment = 'when intact, the form of the item is expected to be broadcast in the beam At least one ratio of electrons; and a detection module 'configured to generate an indication of when the at least portion of the article does not strike the (four)th period of the electrons in the beam to indicate the integrity of the article One of the signs of sexuality. x Embodiments of the invention are not limited to the manufacture of lithographic apparatus, but may be applied to monitor the integrity of any item. This article may have a relatively thin type, such as a 'membrane or screen, and thus tend to acquire holes due to wear or damage. The article can be a flat article or a curved or curved article and can act as a type of filter or barrier between the other article or between two chambers that involve any device that is low or vacuum. Embodiments of the present invention further provide an optical device that includes a system for monitoring the integrity of an item within the optical device. The monitoring techniques disclosed herein can be adapted for other purposes, such as detecting an item outside of the operating environment of the item, or for quality control prior to use: detecting an item being manufactured. Techniques in some embodiments of the invention may also be adapted to the contamination of the surface of the article' or to measure loss of integrity. [Embodiment] Embodiments of the present invention will now be described by way of example only with reference to the accompanying schematic drawings. Various embodiments have been described with reference to the drawings, in which like reference numerals are used to refer to the like. In the above description, numerous specific details are set forth in the description However, it may be apparent that such embodiments may be practiced without these specific details. In other instances, well-known structures and devices are shown in the form of a block diagram in order to facilitate the description of one or more embodiments. Figure! A system 50 for monitoring the integrity of an item in accordance with an embodiment of the present invention is schematically depicted. The system 5 includes an electron beam source module 6A, an object 120, and a detection module 80. The article 12 is located in a low pressure (near vacuum) or vacuum environment defined by the enclosure 9. An example of such an environment is the interior of an EUv lithography apparatus, but of course, vacuum and near vacuum environments are characteristic of many types of scientific and industrial devices, and the present invention is generally applicable to the monitoring of such items. The types of items that can be monitored include, inter alia, extremely thin items (compared to their surface area). Such items that can be classified as membrane-like or screen-like are particularly inclined to form holes due to wear or damage. Embodiments of the invention are also operable to detect contamination of the surface of the article. The electron beam source module 6G is operable to emit an electron beam, and the electrons are represented by a circled _" mark. The electron beam source module 6 is also operative to deliver an electron beam onto the article 12. The controller can be implemented to control the system 5 via a control signal transmitted or wirelessly transmitted through a cable to components of the system 5〇 at various locations within and outside of the vacuum environment. The controller 82 can be part of a controller for a larger device. The portion of the display device is shown in the illustrative embodiment. The electron beam source is 160397.doc 201235796

The stack 60 includes an electron beam source 11 (not shown in Figure 2), and the electron beam source can be, for example, a typical electron grab commonly known in the art of cathode ray tube (CRT) technology. In an example of the invention, the gun may be of the type commonly used for non-wave II CRT, rather than the type used in cRTs for color televisions and surveillance displays. Typically, an oscilloscope will operate at a lower acceleration voltage (eg, in the range of 1 kilovolt to 3 kilovolts, such as 2 kilovolts) compared to a television CRT grab (approximately 30 kilovolts). Leaving the robbing electrons and thus their speed and momentum is usually determined by this voltage, making the oscilloscope electronics travel slower and easier to deflect than electrons from the TV. The invention is not limited to any particular range of electron energies, but is considered to range from 1 kiloelectron volt to 3 kiloelectron volts (e.g., 2 kiloelectron volts) suitable for the application to be described. According to the material properties and dimensions of the article 12, the appropriate energy of the electron beam can be selected over the wide range. The energy of the beam is too high. The beam can make the significant proportion of the electrons have sufficient energy to penetrate the article. . - Generally speaking, if the energy of the beam is set such that all or almost all of the electrons are blocked when the item is intact, then (4) will be easier. In response to directing the electron beam toward the article detection module 80, it is operable to generate an indication of whether there is a hole in the article 12G that would otherwise not be present (ie, 'the item 12 is intact or damaged, and the wall is damaged. Bad) nickname 84. When intact, the item 120 can be configured to block at least a proportion of the electrons in the beam, and the ratio is sufficiently significant that the detection module 80 via the appropriate juice can detect when it is not responsible for the electrons. proportion. Do not know. No. 84 straw identifies when the at least a portion of the item 120 does not block the integrity of the item 120 in the beam. The expected proportion of the electrons is indicative of 160397.doc 201235796 Those skilled in the art should understand that this ratio can occur for the proportion of electrons that can be stopped and for the loss of integrity in articles attributed to wear or damage. The change will greatly depend on the design of the article, the form of the electron beam generated by the source module 6 , the form of the detection module 80, and the scale and nature of the damage or wear that is occurring. In the case of [Embodiment] and the scope of application for a reference to the proportion of electrons that are "expected" to be blocked, this ratio can be determined in different ways and can be expressed differently in the design of the device. This term is only used to indicate that a test is based on the proportion of electrons that are blocked, and is used to distinguish between a complete item or a part of an item that is not complete or part of the item, and does not have a meaning Anything greater. The detection module 80 will perform one or more tests on the detected signals to determine whether an expected ratio of electrons is blocked at a portion of the article to produce an integrity signal 84. For example, in some embodiments, a simple threshold test can be implemented to determine whether to support a predetermined ratio of electrons in the beam. In other implementations, the test can compare the detected signal with the time-varying reference signal instead of applying a fixed threshold. In other embodiments, where the electron beam is directed at different portions of the article at different times, the 'test can compare the signal produced at the portion to the signal at the other portion, or earlier Time is in the same - part of the place immortal ^ signal. It can be applied to the measurement and signal processing technology without departing from the principle of detecting the time when the beam is expected to be emitted (the bean can be simply regarded as the 敎 ratio). Recognize these improvements within the scope. This reference signal can be stored in controller 82 or stored in a test module. , 160397.doc

S • 10· 201235796 Based on this principle, several different types of embodiments are envisaged, and the examples are exemplified below. Detection of electrons passing through the article can be performed in a positive way using a collection element located on the side of the article opposite the source module 60. The electrons transmitted through the article can be detected in a negative way by collecting electrons absorbed by the article. In either case, the detection of electrons can be relatively straightforward (eg, when current is detected in an electrode formed by the collection element or the article itself), or it can be indirect (eg, when a luminescent material such as a phosphor) When it is hit by an electron and emits light that can be detected by a camera or other light sensor). Based on these various possible operational principles, in an exemplary embodiment, the beta module 80 can include a camera and a detection screen that can operate together to obtain signals. In another exemplary embodiment, the detection module 8A can include an ammeter that is operable to obtain a signal. In yet another exemplary embodiment, the detection module 80 can include a combination of a camera's screen and a current meter that can be operated to obtain a signal. The signals referred to herein may be signals that indicate the integrity or non-integrity of the item in a binary manner. The signal can be a variable signal indicative of a non-binary reliability or alarm that can be interpreted by the operator in conjunction with other observations to determine if a protective action is required. It may additionally indicate that a defect (hole) is suspected - or a number of specific locations. The signal output by the monitoring system can be a composite of various signals obtained from different Hs and 7L pieces and/or processed according to different algorithms. The operator of the larger device (the portion of the monitored item 120 forms part of it) will be in the process of determining what action is required in the event of an integrity failure indicated by the L-vision system. In response to the size and/or number of holes detected, the response rate of 16D397.doc 201235796 will depend on the outcome of the fault from the item, and perhaps depending on the extent of the failure indicated. In some cases, integrity The loss can be a loss of yield of the device, or a loss of quality of the product produced by the device. In other cases, the loss of integrity may be a damage to the components of the device itself' and may be a hazard to the operator or the public, or it may be a combination of such. Therefore, in some applications, it may be appropriate to provide an automatic shutdown system that responds to the signal so that once any integrity loss is detected' then the device is shut down during the critical time period. In another application, it may be sufficient to simply record a loss of integrity at least below a certain threshold for reference during planned maintenance time. In the following embodiments, a planar article is used as an example of article 120. However, it will be understood by those skilled in the art that embodiments of the present invention are not limited to application to planar items, but can be applied to monitor the integrity of any item. Naturally, an item that is extremely thin compared to the item in other directions is a type of item that is gradually formed into a hole. Such "thin" items can be considered to be local ground planes (even if they are generally viewed in one or more dimensions). 2 schematically depicts an embodiment of a system for monitoring the integrity of a planar article in accordance with an embodiment of the present invention. The beta system 1 includes an electron beam source 110, a planar article 120, a camera 14 and/or The screen 150 is detected. The electron beam source 110, article 120, and detection screen 150 are located in a low pressure environment or in a vacuum environment. The electron beam source 110 delivers an electron beam represented by a circled "_" mark to the item 120. The entire surface of the part of the item to be monitored or the integrity of the item to be monitored (hereinafter simply referred to as the surface of the item) is covered by an electron beam of 160397.doc -12- 201235796 (by narrow beam across the surface) The sweeping movement is made by filling the entire surface of the article 12 with a wide beam). In an embodiment / electron beam source 110 is, for example, a typical electronic grab as used in an oscilloscope. In this embodiment or in all of the embodiments to be described with reference to Figures 2-7, some or all of the electron beam source 110, and particularly the electronic grabbing itself, may be located entirely or partially in the environment of the item to be monitored 120. Separation of the vacuum loop k in the ground will be described below in a step-by-step manner with reference to FIG. The intact portion of the surface of the planar object 120 absorbs the electrons of the beam. As an example, article I2G can be a separator of metal or other material that will absorb substantially all of the electrons from source m. When the apertures 130 are present in the article 12, the electrons of the beam can pass through the apertures 130. Sources 11 in these embodiments are configured to deliver electrons obliquely to the surface (rather than the self-normal direction) for example, for example, in relation to the form of the article 120 or its function. In the case where the article (10) acts as an element in the radiation beam of the optical system, it may be desirable to have the monitoring system not interfere with the front view and rear view of the item. Alternatively, (4) the oblique incidence of the beam is required so that when the item is intact, the electron is more reliably blocked by the item. An example of this item will be described further below. In other applications, the monthly b can be accessed or the source needs to be placed directly in front of the item. In a case of her, it may be necessary to place the source to a one, but the deflection electrons cause the electrons to collide with the object from a direction perpendicular to the surface. It should be noted that the “uranium side” in this valley does not imply any difference between the two sides of the item: depending on design preferences and practice, the source can be on either side. In this example, the detection screen 15 forming part of the detection module 8〇 is located at 160397.doc 201235796 behind the item 120, that is, in the space traversed by the electrons on the surface of the collision object 12〇. In the opposite space. The surface of the detection screen 15 is coated with a (four) layer 160. In an exemplary embodiment, the metrology layer (10) can be a dielectric layer of the type used in CRTs for oscilloscopes. When the electrons pass through the hole! 3 〇 and impact detection layer (10) 1 layer (10) emits two lights. Camera 140 is positioned to be operable to obtain a 2" image of detection layer 16". In an embodiment t, the camera 140 can be a monochrome camera and can be located in a vacuum environment or positioned outside of a vacuum environment. The optometry (not shown in the figure) can be provided in the camera or in front of the camera to attenuate the wavelength of light other than the wavelength expected by the (4) light body. When the electrons of the beam pass through the aperture 130, the electrons strike the layer (10) and emit light that is imaged by the camera 140. The emitted light shown by the image taken by the camera 14 indicates that there is a hole in the flat article 120. In the case where the source 110 is substantially a point source, the position of the spot in the image is directly related to the position of the hole 13 in the object being monitored. In addition, the image can reveal the size and number of holes that exist across the item in an easily understandable form. The size of the small hole can be judged from the intensity of the spot. The limitation is that the intensity of the electron beam is calculated by calculation or by measurement. (10) The image is processed by automatic signal processing to compare: light: = in) (d) measuring the pattern and predetermined criteria, and generating a signal to report the integrity status of the item 120. FIG. 3 schematically depicts an illustrative system 18 for monitoring the integrity of an item in accordance with another embodiment of the present invention. System 18A includes an electron beam source "〇, planar item 12〇 and camera 140. The electron beam source 11〇, the article 160397.doc 201235796 120 and the detection screen 15 that forms part of the detection module 8〇 are located in a low pressure environment or in a vacuum environment. The surface of the article 120 is coated with a detection layer 160. In an exemplary embodiment, the detection layer 160 can be a fill layer. When the electron impact detection layer 16 is turned on, the detection layer 16 emits light. The camera 140 is clamped to operate to obtain an image of the detection layer j6. Because layer 160 traverses the entire surface of article 12 when article 120 is intact, light is emitted across the field and the camera image is uniformly illuminated. When a hole is present in the article 120, a dark portion of the image can be found. The image seen by camera 140 in this embodiment will effectively be the negative image of the image as seen in the embodiment of Fig. 2. In another embodiment, comparing the 2D image with the reference 2d scene/image of the detection layer 16 obtained when there is no hole in the detection layer 160 can improve the darkness in the recognized 2D image. Partial accuracy. Fig. 4 schematically depicts an exemplary illustration of a system 2〇〇 for monitoring the integrity of a plane object in accordance with yet another embodiment of the present invention. The system includes an electron beam source 110, a planar item 12 and a debt measurement module (10). The detection module 8 includes a debt measurement screen 210 and a measurement device 22 that can be, for example, an ammeter. The electron beam source 110 planar item 120 and the detection screen 21 are located in a low pressure environment or in a vacuum environment. The beta screen 21 is made of a conductive material such that the detection screen 21 can be used to collect the electrodes that pass electrons through the aperture 130. For example, the detection screen can be made of metal. The galvanometer 22G is electrically coupled to the screen 21 〇 for <measures the current level caused by the arrival of electrons from the source 110. The current change (especially increase) according to the current meter 220 indicates that it is stored in the flat object 12

S 160397.doc 15 201235796 Is it possible or not? L. The current level can be interpreted as the size and/or number of #孔孔. In this example t, the electron beam simply fills the surface of the article so that no location information is obtained. In other embodiments described below, the beam is narrower and collides with different portions of the article 12 at different times, for example, to cover the surface of the article 12 in the scanning movement. It should be appreciated that the measuring device 220 can also be, for example, a voltmeter instead of a galvanometer. The voltmeter 220 can be configured to measure the potential of the detection screen 21 〇 relative to the ground. Detection module 80 can include a system configured to reset the potential of detection screen 210, if desired. If the potential change indicator can be measured by the voltmeter 22 在, there is a 孔 in the planar item 120. In particular: 丨 ^ ^ ^ The number of holes exists. When the electron beam is detecting the intact portion of the object 120, the potential of the detection screen 21 is kept substantially constant or the rate of change Rl [v/s] can be changed relatively slowly. When the electron beam traverses the aperture 130 in the article 120, the potential begins to change any such change in the rate of change of the potential of the |r2|>|Ri potential change at a rate of change & [v/s] (also That is, for example, R1 until the change of the value R2) indicates the presence of damage such as the hole 13 〇. It will be appreciated that in the event of scanning the intact surface of the article 12, the rate of change R can be, for example, a predetermined expected rate of change ER. Thus, a change in the rate of change of the potential of the detection screen 210 to a rate of change different from the predetermined expected rate of change indicates the presence of damage. Figure 5 schematically depicts an illustrative illustration of a system 3 for monitoring the integrity of a planar item in accordance with yet another embodiment of the present invention. The system 3 includes an electron beam source 110, a planar object 12 and a detection module 8A. The detection module 8A includes a deflection plate 310, an ammeter 32A, and a voltage source 33A. The electron beam source 110, the planar article 120, and the deflector plate 31 are located in a low pressure environment or in an empty environment of 160397.doc • 16 · 201235796. Instead of using the detection screen 21 shown as system 200, system 3 has a deflection configuration configured to generate an electric field between the two plates 310, 312. The electric field source 330 attracts and collects electrons passing through the holes 13 in the planar article 120 at an electric field disposed between the plates 310, 312. The ammeter 32 is electrically coupled in series with the voltage source 330. The ammeter 32 measures any current change caused by the amount of electrons collected by the plate 31. A change (increase) in current according to galvanometer 32 指示 indicates that a hole may be present in planar item 120. An electric field is used to direct electrons from different holes in the planar article 120 to the plate 31. Therefore, the size of the board 31 in the system 3 is relatively small compared to the detection screen 21 in the system 200. Figure 6 schematically depicts an exemplary system 4 for monitoring the integrity of a planar item in accordance with yet another embodiment of the present invention. System 4 〇 电子 includes an electron beam source 110, a planar item 120, and a metrology module 8A. The detection module 8A includes a metrology device 42 that can be, for example, an ammeter 420. The electron beam source 11 and the planar article 120 are located in a low pressure environment or in a vacuum environment. The flat article 12 is made of a conductive material such as metal. In the detection system 400, the electron beam source of the system is used to describe the surface of the planar object 12 by using a narrow beam rather than by filling the surface of the planar object with a wide beam. The bundle is delivered to a flat item. Electron beam to know the plane items! The part of the surface of the 2 被 is shown as a thorough. When the electron beam hits the planar object 12, since the flat object is made of a conductive material, this situation causes the electronic current to flow. The ammeter 42 is electrically connected to the planar item 120 and measures the current. When the electron beam is scanned through the flat 160397.doc 201235796 face item 120 and passed through a hole i3 that is larger in size than the beam, the beam will pass through the planar item 12 and no current is galvanometer Detection. Thus, in system 400, no current is detected by galvanometer 42〇 indicating the presence of a hole in planar item 12〇. In addition, the timing of the current drop relative to the timing of the scan across the surface of the article can be detected and used as an indication of the location of the hole in the article. The image of the location and size of the apertures can be accumulated in the signal processing unit by scanning the beam with a raster pattern such as a CRT display monitor and recording the current drop synchronously with the scan. The resolution of this image is essentially limited by the narrowness of the electron beam. If there is a hole (which is comparable in size to the beam, but not so large as to pass the entire beam through the hole), the current reduction can still be significant enough to be detected and recognized as an indication of the presence of a hole. In an exemplary system for monitoring integrity, measurement device 420 can also be a voltage leaf configured to measure the potential of article 12G relative to ground. If necessary, the '(4) module 80 may include a potential configured to reset the article 12: when the electron beam strikes the intact portion of the article 12, such as the potential of the article 12 measured by the j. The rate at which the monotonic potential changes is in absolute terms: when the beam is perforated by 13°, the article is dry as any such potential change can be measured by the power plant 420, := There is or may be a hole. As shown in Fig. 4, the implementation can be (:: 120 in the case of a complete surface without a change, (4) ‘, (1), for example, the expected expected rate of change ERi. The change in the rate of change of the variability S π η from the potential of the object ° ° 120 is different from the change in the predetermined expected rate of change ER1 indicates the loss of 16 〇 397.d〇, 201235796. It will be appreciated that due to the electrons absorbed by the article 12, the force will build up, which repels the electrons traveling to the article 120. The accumulation of forces occurs, and the modulus of the potential of the object 120 on the same day rises. In the case of sputum, the potential change rate of the article 12 may be reduced when the electron beam hits or scans the intact portion of the article 120 until the previous reset is performed. When the predetermined expected rate of change ER! is defined and used, the effect of the dependence of the potential change rate of the article 12〇 and the electron beam current dependence can be considered. In addition to obtaining holes due to wear or damage, the item 120 in the operating environment may also obtain contaminating particles 46 on the item 120. Contaminated particles can be made of a non-conductive material. If the electrons strike the contaminating particles 46, the electrons can be absorbed by the contaminating particles 460 without causing the current detected by the ammeter 420. Those skilled in the art will appreciate that the system 400 of the above embodiment, as shown in Figure 6, is operable to monitor the presence of contaminating particles 46 on the article 12. Whether this operation is ideal depends on several scenarios. This embodiment can be adapted to distinguish between contaminants and pores as necessary. One way to make this distinction is to use a combination of detection methods, as will be explained below with reference to Figure 7. Although the differential embodiment has been presented above, those skilled in the art should understand that 'in order to detect and condition the hole in the flat object ,2〇, a practical example of the system can be combined in the system. 1 or more of features 1, 1, 200, 300, and 400. This combination system 5 is shown in Figure 7 as an example that combines the features of the system 18〇 and 4〇〇. These combinations provide more accurate and improved sensitivity in detecting the presence of holes in the planar object gUO and in avoiding false alarms. The system of Figure 7 can be used, for example, to distinguish between contaminant particles 460 and pores in article 120, which is 160397.doc -19 201235796 because: although galvanometer 420 may not be able to distinguish between these different situations, phosphor layer 160 will Electron impact only by the holes passing through the article. In another embodiment, not illustrated, a scanning electron beam of a scanning electron beam similar to the example of FIG. 6 can be used with FIG. 4 or FIG. The detected combination of electrodes 210 or 310 in the example. In this case, the monitoring module can obtain a signal containing information on the position of the hole by comparing the timing of the rise of the electrode current with the position of the electron beam during the scanning of the electron beam. Another technique for improving sensitivity while avoiding false alarms is to apply the electron beam intermittently or in a pulsed manner so that the continuous test module 8 (in whatever form) can be compared to the electron beam. In the case of light and/or current measurements and background levels observed in the event of an electron beam disconnection. Shooting with the camera 14 in the presence of a beam and without a beam =: subtracting the "beam off" image from the "beam on" image before analyzing the image, Can be pushed home to enter this comparison. The frequency or frequency can be known to cause the electron beam to be pulsed' and the number from the camera or electrode can be subjected to chopping' such that other frequencies including DC background levels are reduced; the "hole" signal becomes relatively strong. Electricity can be generated only at known times; shot = pre- and inter-controlled output signals are measured at other times. The operating environment may be known at a frequency or at a known time to provide electron flux or electromagnetic |5-emission output at their known time, or the gate will be reduced for the integrity of the item. The 4 background signal of the baby is ignored and the signal-to-noise ratio is detected when the hole is detected. ~ as the aforementioned electron beam source module 60 - example description 160397.doc

S20.201235796 depicts an electron beam source module 6 according to an embodiment of the invention. The electron beam source module 600 includes an electron beam source 110 and a surrounding envelope of the electron beam source i 1 〇 610 and an opening 62 in the enclosure 61〇. The enclosure 61 defines a separate vacuum or low pressure space within or adjacent to the operating environment of the item being monitored but isolated from the operating environment. In a near vacuum environment containing a small amount of gas (e.g., hydrogen), a high voltage in the electron gun can cause plasma discharge. This situation can prevent proper operation of the source and/or have undesirable consequences elsewhere in the operating environment. By isolating some or all of the source ιι in the enclosure 61, the atmosphere can be controlled to exclude the gas causing the discharge and the discharge is prevented. Except for the difference, the force is maintained substantially equal in both environments, and the dust is separated by a thin window 620, and the electron beam exits through the thin window 620. In order to prevent the electron beam from attenuating too much, the window is made practically thin by materials such as Si, AI, C (diamond) or the like. In embodiments where a narrow electron beam (e.g., for raster scanning in the embodiment of Fig. 6 or Fig. 7) is desired, the beam may become undesirably widened as it passes through the window (4). In order to obtain a narrow beam outside the enclosure 61, a pinhole 630 is provided to select a narrow portion of the electron beam after the electron beam exits from the window 62() as an example - the pinhole diameter may be 0.5 mm or i. Millimeter. The distance between the window 620 and the diameter of the pinhole can be used to determine the angular distribution of the beam. An electron beam from pinhole 630 can be used to scan a planar item (3). The electron beam source module 600 further includes at least a deflection coil 64 that is driven by a suitable circuit (not shown) to generate a time varying electromagnetic field. The electromagnetic field can be deflected, such as by a moving sequence of CRT raster scans.

160397.doc S 201235796 630 electron beam to scan the surface of a flat object 12〇. This scanning motion 45 shown in only one dimension in Figure 8 can be performed in two dimensions to implement the scanning motion 45 使用 used in the system of Figure 6 or Figure 7. It is to be understood that the electron beam source module 000 can further include another collection of deflection coils to produce a second time varying electromagnetic field such that the surface of the planar article 120 can be scanned in two dimensions. In another embodiment, in addition to or instead of imparting scanning motion, an electromagnetic field may be implemented to statically control the size, shape, and/or orientation of the electron beam. The size of the beam can be varied to focus on a wider or narrower portion of the surface of the article. An electron beam deflected by the coil 640 can be used to irradiate the entire surface of the planar article 12〇. Since the deflection is performed with an electromagnet rather than electrostatically, the deflection yoke 640 need not be at a high voltage and can therefore be used in the environment of the article without the risk of plasma discharge in the atmosphere. Since the deflection yoke is located downstream of the pinhole (4), the scanning beam can be extremely narrow and allows extremely sensitive measurements and locations of the hole 13 in the article 12. Application to EUV lithography apparatus Figure 9 schematically depicts a lithography apparatus comprising: a source collector

For example, the anti-residue coating wafer), such as a photomask or a proportional mask, MA, and the first locator 3 of the patterned device, is constructed to hold the substrate (for example, and connected) Up to the second positioner Pw configured to accurately position the 160397.doc -22-201235796 substrate;

And a shirt system (eg, a reflective projection system) ps 'which is configured to impart a pattern of zinc A 3 from the patterned device to the radiation beam 投影 to the substrate W. Part C (for example, containing one or more grains). The illumination system can include various types of optical components for entanglement, sputum or control radiation, such as _!+, c6j_reflection, magnetic, electromagnetic, electrostatic or other types of optical components, Or any combination thereof. The support structure MT holds the patterned device in a manner that depends on the orientation of the patterned device ma, the lithography device, and other conditions, such as whether the patterned device is held in a vacuum environment. Work, static or other clamping techniques to hold the patterned device. The building structure can be, for example, a frame or table that can be fixed or movable as desired to ensure that the patterned device is, for example, in a desired position relative to the projection system. The term "patterned device" should be interpreted broadly to refer to any crying that can be used to impart a pattern to a light beam in the heart's section of the radiation beam to create a pattern in the target portion of the substrate. 15 pieces. The pattern imparted to the radiation beam may correspond to a device created in the target turret (such as an integrated functional layer. The patterned thief may be transmissive or reflective. Examples of patterned devices include reticle Programmable mirror arrays, and programmable LCD panels. Photomasks are well known in lithography and include reticle types such as binary, alternating phase shift and attenuated phase shifts, as well as various hybrid mask types. Programmable Mirror Array - Examples use a small mirror matrix configuration, each of the small mirrors

S I60397.doc -23 201235796 has been tilted individually to reflect the incident light beam in different directions. The tilted mirror imparts a pattern to the radiation beam that is reflected by the mirror matrix. As with the illumination system, the projection system can include various types of optical components suitable for the exposure radiation used or other factors such as the use of vacuum, such as refractive, reflective, magnetic, electromagnetic, electrostatic or other types of photonic components, Or any combination thereof. It may be necessary to use vacuum for euv radiation because other gases may absorb excessive radiation. Therefore, the vacuum environment can be supplied to the entire beam path by means of the vacuum wall and the vacuum pump. As depicted herein, the device is of the reflective type (e.g., using a reflective reticle). The lithography device can be of the type having two (dual stage) or more than two substrate stages (and/or two or more reticle stages). In such "multi-stage" machines, additional stations may be used in parallel or preparatory steps may be performed on - or multiple stations while one or more other stations are used for exposure. > See Figure 9 for the 'light system IL from the source collector module s〇 receiving the extreme ultraviolet radiation beam. Methods for producing EUV light include, but are not necessarily limited to, those used in the EUV range - or a plurality of emission lines to convert a material having at least - an element (e.g., 'gas, war or tin) into a plasma state. In one such method (commonly referred to as laser generating electricity "Lpp"), the fuel can be irradiated with a laser beam (such as droplets, strings of material having the desired spectral emission elements). Flow or clustering) produces the required electricity I. The source collector module S0 can be a component of an EUV light-emitting system that includes a laser (not shown in Figure 4) for providing a laser beam that excites the fuel. The resulting plasma emission output: shot (eg, (4)), which is used in the source collector module.

S -24- 201235796 ' When a co2 laser is used to provide a source and source collector module, it can be collected for the separation collector. For example, when a fuel-excited laser beam, the Ray ° entity. In this special case, the parts that do not form a lithography device for the laser are not cut, and the radiation beam is by means of a beam delivery system comprising, for example, a sigma-guided mirror and/or a beam expander. From the laser to the source collector module. In other situations, such as when the source is a discharge generating a plasma EUV generator (often referred to as a source), the source can be an integral part of the source collector module. The illumination system IL may comprise an adjuster that uses #雅M a : an angular intensity distribution of the jade radiation beam. Typically, the intensity distribution in the pupil plane of the illumination system can be adjusted to be outside of v. P is only in the dry and/or inner radial range (usually referred to as the exterior of the mouth and the interior of the σ, respectively). In addition, the illumination system IL can include various other components, such as a faceted field mirror device and a faceted mirror device. The illumination system can be used to adjust the beam of ray to have the desired uniformity and intensity distribution in its cross section. The radiation beam Β is incident on a patterned device (eg, reticle) MA that is held on a support structure (eg, & reticle glare), and is patterned by the patterned device. | Self-patterning After the device (eg, reticle) is comfortably reflected, the radiation beam B is passed through the projection system ps, which projects the beam onto the target portion c of the substrate w. By means of the second positioner pw & position sensor PS2 (For example, 'interference measuring device, linear encoder or capacitive sensor', the substrate table WT can move accurately, for example, to position different target portions C in the path of the radiation beam] 3. Similarly, first The positioner pM and the other position sensor PS 1 can be used to accurately position the patterned device (eg, reticle) MA with respect to the path of the radiation beam b. The reticle alignment can be used. The M1, M2 and substrate alignment marks P1, P2 are used to align the patterned device (eg, photomask) MA and substrate W » the depicted device can be used in at least one of the following modes: 1. In step mode In the entire pattern to be given to the radiation beam once When projecting onto the target portion c, the support structure (for example, the reticle stage) MT and the substrate stage Wt are kept substantially stationary (ie, a single static exposure). Next, the substrate stage WT is oriented in the X and/or Y direction. Upshifting so that different target portions c can be exposed. 2. In the scan mode, 'synchronously scan the support structure (eg, the mask table) when the pattern to be imparted to the radiation beam is projected onto the target portion c Substrate table WT (ie, single dynamic exposure). The speed of the substrate table WT relative to the support structure (eg, the mask table) MT can be determined by the projection system with the magnification (reduction ratio) and image reversal characteristics. And the direction t in another mode, when the pattern to be imparted to the radiation beam is projected onto the boring tool c, the support structure (eg, the reticle stage) mt is kept substantially stationary 'to maintain the programmability Patterner #, and move or scan the substrate: WT. In this mode, a pulsed light source is typically used and updated as needed between each movement of the substrate table WT or between successive pulses of radiation during the scan. Programmable patterning This mode of operation can be readily applied to matte lithography utilizing a programmable patterning device, such as a programmable mirror array of the type mentioned above. The use described above can also be used. Combinations of modes and/or variations or completely different modes of use. 160397.doc • 26- 201235796 Figure 10 shows a schematic side view of an embodiment of an EUV lithography apparatus 700. It should be noted that although the physical configuration is different from that shown in Figure 9 The physical configuration of the device, but with the same module and similar operating principle. The device comprises a source collector module s in the vacuum housing 703, an illumination system IL in the vacuum housing 7〇4 and in the vacuum housing 705 Projection system ps. In the source collector module is a radiation source 707 in which a very thermal discharge plasma is created from a gas or vapor (such as a heart gas or Li, Gd or Sn vapor) for emission in the EUV range of electromagnetic radiation Radiation. In the illustrated Dpp type source, discharge electropolymerization is created by causing a portion of the ionized plasma causing the discharge to collapse onto the optical axis. For the efficient production of light shots, Xe, Li, Gd, Sn steam or any other for a partial pressure of, for example, 1 〇 Pascal (〇.1 mbar) may be required.

Beta gas or steam. In an embodiment, the Sn source is applied as an EUV source. Instead of the DPP source 707', an LPP source can be used in which C〇2 or other lasers are directed and focused into the fuel ignition zone. The laser beam generator can be an eh laser having an infrared wavelength (e.g., 1 〇 6 μm or 94 μm). Alternatively, other suitable lasers having respective wavelengths in the range of 丨 micrometers to 丨丨 micrometers can be used, for example. After interacting with the laser beam, the fuel droplets are then transformed into an electrical destruction state. The state of the electricity can be emitted, for example, by 6.7 nm, or selected from the range of 5 nm to 20 nm. Other Euv radiation EUVs are examples of interest here, but different types of radiation can be produced in other applications. The radiation generated in the plasma is typically collected by a normal incidence collector (e.g., an elliptical or other suitable collector). The radiation emitted by the radiation source 707 is via a gas barrier or a "foil cut"

The contaminant trap 709 in the form of a "reservoir" is transferred to the collector optics. The purpose of this contaminant trap is to prevent or at least reduce the incidence of degradation of the effectiveness of components such as time (4) and (4) of the materials or by-products that collide with the optical system. Examples of such contaminant traps are described in U.S. Patent Nos. 6,6u, 5G5 and (4). The construction of such contaminants is not critical to the understanding of the present invention. In some versions, such contaminant traps can contribute to the presence of low vacuum enclosures 7〇3. The radiation collector 708 is, for example, a nest comprising a so-called grazing incidence reflector: an array of grazing incidence collectors. Lightweight collectors suitable for this purpose are known from the prior art. Alternatively, & it has been mentioned that the device may comprise a normal incidence collector for collecting radiation. The deleted light beam emitted from the collectors 7〇8 will have a certain angular spread' perhaps up to ι degrees on either side of the optical axis. The light from the source collector housing 703 is focused in the virtual source point 712 (i.e., in the intermediate focus or IF) and enters the housing 7'4 of the lighting system. The radiation beam 716 is reflected by the normal incidence reflectors 713, 714 in the illumination system to a proportional reticle or reticle that is positioned on the proportional reticle or reticle stage. A (4) chemical beam 717 is formed which is imaged by the projection system ps via reflective elements 718, 719 onto a substrate mounted on a wafer stage or substrate table WT. In general, more components than the components shown may be present in the illumination system IL and the projection system Ps_. Chlorine or other gases may be provided at other points in the lithography apparatus as barriers or bumpers for the anti-purple contaminant particles. In detail, hydrogen can be configured to source 160397_doc

S -28- 201235796 Sets the IsA group SO's maneuvering of the ^A τ in a near vacuum environment to impede the possible attempts to pass the particles in the Yiwangquan system through the intermediate focus (IF) pores. In addition, the f gas can be deployed in the vicinity of the (1) patterned device (eg, reticle) support MT as a buffer against the contamination mask of the system, and deployed in the vicinity of the (8) wafer support WT as an anti-violet Buffers from the wafer enter the buffer of the larger vacuum space within the system. For all this purpose, the fish v. One, the original HS (the source of some sources is not painted schematically), some of the hydrogen sources are not indicated, and all of them are slammed. To supply hydrogen to each contaminant trap configuration - you can supply molecular hydrogen (H2) as a simple buffer, while other sources produce helium free radicals. The invention is not limited An embodiment having a chlorine atmosphere. The crucible is referred to as another gas that can be used in the contaminant trap. Spectral purity chopper as an item to be monitored In an embodiment in accordance with the invention, the EUV lithography apparatus 7 Included in one or more spectral purity filters (SPF), including, for example, in the illumination system IL; a light state 720 or a chopper 71 in the source collector module 〇. A spectral purity filter is known to the art. Figure 丨〇 shows an embodiment of the spectral purity filter 710 as a transmission type rather than a reflective grating. Under this condition, the radiation from the source collector module SO follows the self-collector. Straight path to the intermediate focus IF (virtual source point). In one embodiment, the radiation traversing the collector 708 can be reflected off the grating spectral filter to focus in the intermediate focus IF. In this case, the optical path is not straight, but instead is SPF by reflection type. Alternatively, or in addition, a filter such as filter 720 can be placed downstream of virtual source point 712. Multiple filters can be deployed. 160397.doc • 29· 201235796 For example, 'can be implemented behind SPF A reflection type filter and/or an absorption type filter to attenuate unwanted spectral components in the optical path. The term "transmission" as used with respect to SPF means that the desired radiation (eg, EUV radiation) is substantially transmitted through the filter. Instead of wanting radiation to be substantially blocked 'whether by reflection, absorption, or a combination of both. This special function; the function of the optical filter is to minimize the amount of unwanted wavelengths of the radiation in beam B' where only EUV radiation is desired. Depending on the type of source 707 used, many wavelengths other than EUV are desired to be strongly present in the radiation. There may be radiation at DUV and visible wavelengths. In an infrared-based LPP source, for example, in addition to generating any kind of radiation in the plasma, a large amount of infrared radiation is also present. The unwanted wavelength of radiation transmitted through the device can substantially directly impair the imaging performance of the device. In addition, the large amount of radiation at undesired wavelengths will generally contribute to unnecessary heating of optical components and environments such as components 713, 714, 718, and 719. Not only will the components be distorted and thus cause poor imaging, and this teaching will usually be sufficient to cause permanent damage to the precision components or patterned components of the device. / The embodiment of the present invention - the article (10) may be a transmission type photometric filter ("SPF") such as a grid type SpF grid or a diaphragm type. In an embodiment, purely by way of example, spF7u) is deployed by the master 2 to block (or at least reduce) the infrared wheel into the lighting system. The SPF 720 is deployed in the lighting system to block or = Reduced bed UV (UV) light shot diaphragm type coffee. Both of these talks are of the transmissive type and take the form of large flat objects placed in the plane of the transverse beam of radiation, 160397.doc 201235796. Even very small holes in the transmissive SPF can still allow unwanted radiation to pass through. In the environment within the source collector module s or the housing 703, 704 of the illumination system IL, detection of spF by direct observation can be difficult. Even in the case where a camera can be installed to observe the filter, the distortion that occurs during operation and the structural features such as the grid pattern in the grid type spF can make it difficult to distinguish between the damaged filter and the intact filter. . False alarms from integrity monitoring systems can be extremely costly in terms of lost yield and should be minimized as much as possible. In EUV lithography apparatus 750, systems 5 and 52 are operable to monitor the integrity of filters 710 and 720, respectively. Each of the systems 5 and 52 can be any of the integrity monitoring systems described above with reference to Figures 1-8, or a combination thereof. In consideration of the risk of damage associated with the failure of 7K and each of the pulverizers, depending on the effectiveness of different monitoring systems under different conditions and the constraints of space and cost, each filter can be Deploying Different Monitoring Systems β In the case where the SPF 720 is a diaphragm type SPF for EUV lithography, the diaphragm opens > the planar item 120, the integrity of the planar item 120 to be monitored using the integrity monitoring system 52. A simple example of this diaphragm type SPF is a metal diaphragm, for example, a zirconium diaphragm. Figure U depicts an illustrative illustration of a Monte-Carlo simulation of electron trajectories after electrons impact a ruthenium membrane, where the electron beam is directed perpendicular to the surface of the membrane and has an energy of 2 kiloelectron volts (corresponding to electron velocity) ). In the figure, no electrons penetrate deeper than 50 nm' and thus the electrons are reliably absorbed by the separator. When the aperture 13 出现 appears in an even small size, the electrons can pass as illustrated in Figures 2 to 7 160397.doc 31 201235796 and the aperture can be detected by the integrity monitoring system. In embodiments of the diaphragm type SPF for EUV lithography, the simple barrier film may be replaced by another metal or by a multilayer structure or metal and/or other materials such as ruthenium. An example of a multilayer SPF is disclosed in European Patent Application Publication No. 2053464 A. As mentioned above, the electron beam energy should be selected with respect to the material properties and dimensions of the article. In multilayer diaphragm SPF, these properties depend on the combination of thickness and material. The material properties of the item 120 include, for example, the charge and abundance of the elements used for the item 120. For example, to achieve the same penetration depth, for a diaphragm made of heavier elements, the electron beam source module 60 can be adjusted to produce an electron beam with lower energy, while for items with lighter elements 120. The electron beam source module 60 is operative to generate an electron beam having a higher energy. The optimum energy value to be used can be determined experimentally. In the case where the SPF 710 is a grid type SPF for EUV lithography, this grid forms a planar item 120, and the integrity of the planar item 120 is to be monitored using the integrity monitoring system 52. An exemplary raster type SPF will be described with reference to Figures 12 and 13 . It will be seen that the grid type SPF already includes very small pores that allow some electrons to pass through. When the aperture 130 occurs above a normal size, more electrons can pass as illustrated in Figures 2-7, and the aperture can be detected by the integrity monitoring system 50. Figure 12 is a front elevational view of a portion of an exemplary spectral purity filter component 802 made in accordance with U.S. Patent Application Serial No. 61/193,769, the entire disclosure of which is incorporated herein by reference. The application is an SPF component of a lithography apparatus. Filter component 802 is configured to transmit extreme ultraviolet 160397.doc -32 - 201235796 line (EUV) radiation while substantially blocking the second type of radiation (unwanted) radiation generated by the radiation source. This unwanted radiation can be, for example, an infrared (IR) light shot having a wavelength greater than about 1 micron (especially greater than about 1 G micron). The desired EUV radiation to be transmitted and the second type of unwanted radiation (to be blocked) may be emitted from the same radiation source (e.g., source 微 of the lithography apparatus). Fig. 13(a) is a schematic front view of a very small area in the filter component of Fig. 12, and Fig. U(b) shows the same part in a cross section on the line Β·Βι. In the example to be described, the 'light 4', the purity chopper comprises a substantially planar photoreceptor part (e.g., a photoreceptor film or a chopper layer). The chopper component has a plurality of (substantially parallel) apertures 9〇4 to transmit extreme ultraviolet radiation and to inhibit transmission of the second type of radiation. The surface from which the radiation is radiated from the source S 将 will be referred to as the front surface, and the surface from which the radiation exits to the illumination system IL may be referred to as the back surface. In the illustrated example, each aperture 904 has parallel side walls 〇6 that define apertures 9() 4 and extend completely from front to back. As seen in Figure 2, structural member 808 can extend between portions of grid member 8〇2 such that the filter components are not too brittle to traverse the entire beam path. The filter member 8〇2 can be only a few microns thick while extending over a straight position of a few centimeters. The filter component may be made of a metal such as tungsten (w), which in this case is inherently electrically conductive and suitable for capturing and conducting electrons: in embodiments of the monitoring system in which the article itself acts as a conductor for monitoring current, simple It is necessary to electrically connect the filter components 802 to collect current. It may be necessary to insulate the filter components from their mounts to allow current collection (unless current can be collected through the mount). 160397.doc -33- 201235796 In other embodiments, the filter component 802 can be made of a non-metallic material. For example, 'the grid SPF has been proposed. In such embodiments, the optometer components can be modified to ensure that the filter components capture electrons to the extent necessary to properly function the monitoring system. If the monitoring system is of the type in which the item itself is used as a conductor for monitoring current, the same or different modifications may be made to ensure proper conduction of the electrons. For example, niobium parts can be doped to ensure conduction. In some embodiments, the filter component made of tantalum will have been coated with a metal such as molybdenum (Mo) to aid in the reflection of infrared radiation. The same coating can be used to adequately capture and conduct electrons to allow proper functioning of the integrity monitoring system. The filter components can be modified by the addition of a phosphor layer 160, which is based on the embodiment of Figure 3. Figure 14 (a) depicts the electron beam delivered in the direction perpendicular to the surface of the grid type filter of Figure 3. Although some electrons can be absorbed by the filter, a significant proportion of the electrons pass through the apertures 9〇4 without contacting the side walls 9〇6. When there are holes 13 in the grid type filter, the proportion of electrons passing through the holes 130 and the apertures 904 is increased in principle, which may in principle be by any of the above systems or a combination thereof (such as The detection module 80) of the system 5 detects. However, in this example, the electronic flux difference between the damaged condition and the undamaged condition can be relatively small, making it challenging to design the monitoring system to detect the small aperture 130 without risking false alarms. Figure 14 (b) depicts an electron beam delivered at an oblique angle to the grid type filter. The electron beam is delivered to the grid type filter at an angle to the side walls 9〇6. In this case, the electrons hit the side walls 9〇6. In their electrons 160397.doc -34· 201235796, although some electrons are absorbed by the filter due to contact, some electrons bounce along the side wall 9〇6 before passing through the grid type filter. . In embodiments where the item itself does not act as a detector or is not a unique detector, some or all of these electrons may be detected by the integrity monitoring device. When the apertures 130 are present in the grid type filter, the amount of electrons passing through the apertures 13 and 904 is different, and the difference can be achieved by any of the above integrity monitoring systems as an embodiment of the system 5A. Or a combination of them. Since the beam is delivered at an angle to the filter, more of the electrons of the electron beam are absorbed by the filter (in its intact portion) and the difference detected is compared to when the electron beam The difference detected when perpendicular to the filter can be significant. In a further alternative embodiment, the SPF can be physically located anywhere in the radiation path. In an embodiment, the SPF is located in a region V that receives EUV radiation from an Euv radiation source and delivers EUV radiation to a suitable downstream EUV radiation optical system, wherein the radiation from the EUV radiation source is configured to pass through before entering the optical system SPF. In one embodiment, the spF is in an Euv radiation source. In one embodiment the 'SPF is in an EUV lithography apparatus, such as in an illumination system or in a projection system. In an embodiment, the SPF is located in the radiation path after the plasma but before the collector. It should be understood that the apparatus of Figure 1 can be used in a lithography manufacturing process in conjunction with one or more systems for monitoring the integrity of planar items. The lithography apparatus can be used to manufacture 1C, integrated optical systems, guidance for magnetic domain memory and detection patterns 'flat panel displays, liquid crystal displays (LCDs), thin film magnetic heads, and the like. It should be understood that 'in the context of the content of such alternative applications, 160397.doc -35- 201235796 is used herein for any use of the "wafer" or "die" and the more general term "substrate" or The "target part" is synonymous. The substrates referred to herein may be processed before or after exposure, for example, in a coating development system (a tool that typically applies an anti-money agent layer to a substrate and develops the exposed resist), a metrology tool, and/or a detection tool. . Where applicable, the disclosure herein can be applied to 4 and other substrate processing tools. Alternatively, the substrate can be processed more than once (for example) to create a multilayer 1C, such that the term "substrate" as used herein may also refer to a substrate that already contains a plurality of treated layers. It will be understood by those skilled in the art that the integrity monitoring system 50, 52 is not limited to monitoring only the source collector unit s of the EUV lithography apparatus or the SPF in the illumination system IL. System 50 can be implemented to typically monitor the integrity of any or other items in the Euv optical device, or to monitor the integrity of any spF or other item in any device that requires the item to function in a vacuum or near vacuum environment. Alternatively, for example, the system 5 can be implemented outside of the operating environment of the Euv lithography apparatus to monitor the item 120 before or after the item 12 is operated in the EUV lithography apparatus, or in the manufacturing process of the item 12 The item 120 is monitored as a quality control. The above description is intended to be illustrative, and not restrictive. Therefore, it is to be understood that the invention described herein may be modified without departing from the scope of the appended claims. For example, the above illustrative example can be implemented to detect the integrity of a curved article. The curved article can be, for example, a grid type (four) 'optical device in an optical device such as an EUV lithography. The following illustrative embodiments of the invention are disclosed. In a consistent application, a means for monitoring operations in a low pressure environment is provided.

S. 36_201235796 - A method of integrity of an article, the method comprising: directing an electron beam toward the item in the environment, the form of the item being configured to block the in the beam when intact At least a significant proportion of the isoelectronics; and generating a signal indicative of the integrity of the article by at least a portion of the article that does not block the (four) ratio of the electrons in the beam. In some embodiments, the signal is generated, at least in part, by detecting a current flowing in the article itself, a decrease in one of the currents indicating that more electrons are expected to pass through the article. The electron beam can be directed at different portions of the article at different times, and wherein the timing of the current drop is used to produce a signal indicative of a portion of one of the defects in the article. For example, the electron beam can be directed at the article in a raster scan pattern. In some embodiments, a collecting electrode is positioned to collect electrons transmitted through the article, and wherein the signal is generated, at least in part, by detecting a current flowing in the collecting electrode, one of the currents being raised An electron indicating more than the expected electron is being passed through the item. In these embodiments, the electron beam can be directed at different portions of the article at different times, and wherein the timing of the current rise can be used to generate a signal indicative of a location of one of the defects in the article. . For example, the electron beam can be directed at the article in a raster scan pattern. In some embodiments 'a phosphor is applied to one or more of the elements in the path of the electron beam, and wherein at least in part is observed by the phosphor when it is impacted by the electron beam This signal is generated by light. In these embodiments, the electron beam can be directed at different portions of the article 160397.doc 201235796 at different times, and wherein the timing of one of the emitted lights can be used to generate a defect indicative of the article A signal from one part. The phosphor can be applied to a collection screen configured to receive electrons passing through the article, one of the light patterns formed on the collection screen indicating the presence of a defect in the article. In some embodiments, the electron beam is generated by an electron source in a vacuum or low pressure environment that is substantially isolated from the environment of the article itself. In this embodiment the environment of the article can include hydrogen at a low pressure, and the environment of the electron source can substantially exclude the hydrogen. The electron beam can be modified by an electromagnetic configuration after entering the environment of the item. The electromagnetic configuration can be controlled to deflect the electron beam to different portions of the article at different times. In one embodiment, the electron beam transmitted through a aperture is narrowed prior to being deflected by the electromagnetic configuration. In some embodiments, the article is operated within an EUV optic. In such embodiments, the article is operable within an Euv lithography apparatus. For example, the article can be a spectral purity filter constructed to attenuate radiation at wavelengths other than one of the EUV wavelengths. In one embodiment, the article is a membrane or foil. In another embodiment, the item is in the form of a grid. In one embodiment, the electron beam is directed at the article at an angle away from one of the planes perpendicular to the object. In some embodiments, a system for monitoring the integrity of an item operating in a low pressure environment is provided. In these embodiments, the system package >6〇397.d〇c -38 - 201235796 includes an electron beam source module and a detection module, the system being operative to perform the above-described embodiment Any of the methods. In some embodiments, an optical device is provided, the optical device comprising: a radiation unit for providing an EUV radiation beam through an exit aperture; an illumination system for the exit aperture from the radiation unit Receiving the EUV radiation beam and for adjusting the beam to illuminate a patterned device, a projection system for producing an image of the illuminated patterned device on a substrate for use in EUV lithography Transferring a pattern from the patterned device to the substrate; at least one of the systems of any of the above-described embodiments for monitoring the integrity of a filter in the lithography apparatus, wherein A filter is located in the path of the radiation beam in one of the radiation unit, the illumination system, and the projection system. Although specific embodiments of the invention have been described above, it should be understood that the embodiments described herein may be implemented in hardware, software, intermediate software, microcode, or any combination thereof. For example, the present invention can take the form of a computer program containing one or more sequences of machine readable instructions that, when executed by a computer, control the components of the system described above to monitor the integrity of the article. . μ For hardware implementation, the processing unit can be implemented in one or more special application integrated circuits (ASICs), digital signal processors (Dsp), digital signal processing devices (DSPDs), programmable logic devices. (pLD), Field Programmable Gate Array (FPGA), processor, controller, microcontroller, microprocessor, other electronic units designed to perform (4) described herein, or a combination thereof. 160397.doc •39- 201235796 When implementing these physical warehouses in software, industy, 中间 intermediate software or microcode, code or program segment, these embodiments may be stored in such a way as to The machine-readable medium φ ^ that holds the group in the body. The code segment can represent a program, a multi-program, a routine, a subroutine, a module, a package software, a category instruction, a data structure, or a combination of materials. ^ or receiving information, data, and arguments. Transfer a program & amp to the other code segment or hardware. You can use any suitable method (including memory sharing, messaging, token delivery, network transmission, etc.) to pass, forward, or transmit information, arguments, and so on. For software implementations, the techniques described herein can be implemented with modules (e.g., programs, functions, etc.) that perform the functions described herein. Software, code: stored in the domain unit and executed by the processor. The memory unit can be implemented within the processor or external to the processor, in the latter case: 'the memory unit it can be lightly coupled to the processor via various means as is known in the art. The terms "including" and "including" as used in the scope of the claims do not exclude other items or steps. The term "a" as used in the scope of the patent application does not exclude the plural. The above description is intended to be illustrative, and not restrictive. Therefore, it will be apparent to those skilled in the art that the invention described herein may be modified without departing from the scope of the invention. BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 schematically depicts an embodiment of a system for monitoring the integrity of a system for monitoring the integrity of an item in accordance with an embodiment of the present invention. FIG. 3 is a schematic depiction of a system for monitoring the integrity of an article according to the present invention for monitoring one of the embodiments of Pingming; FIG. 3 is schematically depicted in accordance with the present invention. System for the integrity of an item; Figure 4 schematically depicts a system according to the integrity of the present article; Figure 5 schematically depicts a system according to the integrity of the present article; Figure 6 is schematically depicted in accordance with the present invention An exemplary system for monitoring the integrity of a planar item; FIG. 7 schematically depicts an exemplary system for monitoring the integrity of a planar item in accordance with an embodiment of the present invention; FIG. 8 is schematically An exemplary electron beam source module is depicted in accordance with an embodiment of the present invention; FIG. 9 schematically depicts the main features of an EUV lithography apparatus; FIG. 10 shows a schematic side of an exemplary EUV lithography apparatus. Figure 11 depicts a Monte-Carlo simulation of electron scavenging after electron impact on a zirconium diaphragm from an example of a silver-purity filter component in the EUV lithography apparatus of Figure 10; Figure 12 is a grid type spectral purity filter A front view of a portion 8 of another example of an optic component; Figure 13 (a) is a schematic front view of a smaller region within the grid type spectral purity filter component of Figure 12; 160397.doc

S -41 · 201235796 Figure J 3 (t >) is a cross-sectional view of the same area as shown in Figure 13 (a). Figure 14 (a) depicts the surface perpendicular to the grid type filter ' < °卩An illustrative illustration of an electron beam that divides and ma; and FIG. 14(b) depicts an illustrative illustration of an electron beam delivered at a portion of the surface of the grid type filter. [Main component symbol description] System/integrity monitoring system for monitoring the integrity of items 52 Integrity monitoring system 60 Electron beam source module 80 Debt test mode and 82 Controller 84 Integrity signal 90 Enclosure 100 for monitoring planes, 110 electron beam source 120 monitored items/plane 130 holes 140 camera 150 detection screen 160 detection layer/phosphor layer 180 for monitoring items 200 for monitoring planes 210 detection screen / Electrode 160397.doc

• 42· S 201235796 220 300 310 312 320 330 400 420 450 460 500 600 610 620 630 640 700 703 704 705 707 708 709 Measuring device / galvanometer / voltmeter / electrode for system deflection for monitoring the integrity of flat objects Slab galvanometer voltage source for monitoring the integrity of planar objects. Illustrator system / detection system galvanometer / measuring device / voltmeter scanning motion pollution particles / pollutant particle combination system electron beam source module enclosure opening /Thin window pinhole deflection coil extreme ultraviolet (EUV) lithography device vacuum enclosure vacuum enclosure vacuum enclosure radiation source / DPP source radiation collector contaminant interceptor 160397.doc -43- 201235796

710 712 713 714 716 717 718 719 720 802 808 904 906 BC HS IL Ml M2 MA MT O PI Collector Optics / Spectral Purity Chopper (SPF) Virtual Source Point Normal Incandescent Reflector / Component Normal Incandescent Reflector / Component Radiation beam via patterned beam reflection element Reflective element Spectral Purity Filter (SPF) Spectral Purity Filter Part/Grid Part Structure Part Pore Parallel Sidewall Radiation Beam Target Part Hydrogen Source Illumination System Mask Alignment Marker Light Shield alignment mark patterning device support structure/proportional reticle or light|stage/patterned struts optical axis substrate alignment mark 160397.doc

S * 44 - 201235796 P2 Substrate alignment mark PM First positioner PS Projection system PW Second positioner SO Source collector module / Laser generated plasma (LPP) source / source collector unit W Substrate WT Substrate table / Wafer support 160397.doc • 45-

Claims (1)

201235796 VII. Scope of application for patents: 1. A method for monitoring the integrity of an item operated in ^_ /rf ® IS I (4) low house mystery' method includes: :::-electron beam towards the environment The article, when the intact form is configured to block at least a proportion of the electrons in the beam; and the ratio IJ is based on the electrons of the beam that are burned to the article Generating to indicate the integrity of the item. 2. The method of claim 1 is 丄Wu σ, at least in part by detecting a current flowing in the mouth of the object. f 5 唬, one of the current reductions means that no eve electrons are passing through the article. 3. The method of claim 1, wherein the middle arm/the middle one collects an electrode for receiving electrons passing through the article, and at least partially by the hybrid power, the current And to generate the signal, the current-increasing heart is not passing through the item. 4. In the method of claim 2 or 3, the basin is guided at different times in the (four) port and at different times to guide the electron beam at different portions of the mark, ^ ^ using any current to change one of the timings to generate Indicate the medium number of the item. A letter from one of the defects 5. As requested! To any of the methods of 3, 兮雪工aa', a layer of phosphor applied to one of the paths of the 泫 electron beam or 70 pieces, and at least part of which is determined by the speculation The signal is generated by the nine-light emission of the electron light. The article is operated by the method of any one of claims 1 to 3, wherein the S160397.doc 201235796 EUV is optically placed in the farm. 7. The method of claim 6, wherein the article is a filter within the EUV optics. 8. A system for monitoring the integrity of an item operating in a low pressure environment, comprising: an electron beam source module configured to direct an electron beam toward the item within the cassette The form of the item is configured to block at least a proportion of the electrons in the beam when intact; and a detection module 'configured to be at least partially based on being blocked by the item The ratio of the electrons of the δ ray beam produces a signal indicative of the integrity state of the item. The system of claim 8, wherein the debt testing module comprises an galvanometer, and the signal is generated by using the galvanometer to extract a current flowing in the article itself, and the current is reduced. Indicates that more electrons are passing through the item. 10. The system of claim 8, wherein the detection module includes a collection electrode to collect electrons transmitted through the article, and wherein the current flowing in the collection electrode is detected, at least in part, by using a collection electrode And generating a "Hing L, the increase in one of the currents indicates that more electrons are being passed through the article. 11. The system of any one of clauses 8 to 10, wherein the detection module is operable to be different The time directs the electron beam at a different portion of the article, and wherein any timing of the current change is used to generate a signal indicative of a location in the article - the defect. The system of any one of claims 8 to 1 wherein the detection module includes a phosphor applied to one or more of the elements in the path of the electron beam. And generating the signal at least in part by observing the light emitted by the phosphor when it is struck by the electron beam. 13. The system of any one of claims 8 to 1 wherein the article is operated in an EIJV optical device. 14. The system of claim 13 wherein the item is a filter within the EUV optics. 15. An optical device comprising: a radiating element for providing an EUV radiation beam through an exit aperture; an illumination system for receiving the EUV radiation beam from the exit aperture of the radiation unit A projection system for illuminating a patterned device; a projection system for generating an image of the illuminated patterned device on a substrate to transfer a pattern from the patterned device by EUV lithography And a system for monitoring the integrity of a filter in the lithography apparatus, wherein the filter is located in the radiation unit, the illumination The path of the radiation beam in the system and one of the projection systems. 160397.doc