Inspection device

Abstract

An inspection apparatus for inspecting an object, such as a pellicle, for use in an EUV lithographic apparatus, the inspection apparatus comprising:-a vacuum chamber; -a load lock forming an interface between the vacuum chamber and the ambient environment; -a platform device configured to receive the object from the load lock and to displace the object within the vacuum chamber; wherein the vacuum chamber comprises a first parking position and a second parking position for temporarily storing the object.

Description

[0001] This application is a divisional application of the patent application with the application number 201980069782.5, the invention name of "inspection equipment", and the date of entry into the Chinese national phase on April 22, 2021 (the international application date is October 17, 2019, and the international application number is PCT / EP2019 / 078152). Technical Field

[0002] The present invention relates to an inspection tool or equipment that can be used to inspect an object, in particular, the object is an object used in the manufacture of integrated circuits using EUV lithography equipment. In particular, the inspection tool or equipment can be used to inspect the surface film used in EUV lithography equipment to protect the patterned mask from contamination. Background Art

[0003] A lithography apparatus is a machine configured to apply a desired pattern onto a substrate. A lithography apparatus can be used, for example, in the manufacture of integrated circuits (ICs). A lithography apparatus can project a pattern at a patterning device (e.g., a mask) onto a layer of radiation-sensitive material (resist) provided on a substrate, for example.

[0004] To project a pattern onto a substrate, a lithography apparatus can use electromagnetic radiation. The wavelength of this radiation determines the minimum size of the features that can be formed on the substrate. Compared to a lithography apparatus using radiation having a wavelength of, for example, 193 nm, a lithography apparatus using extreme ultraviolet (EUV) radiation having a wavelength in the range of 4 to 20 nm (e.g., 6.7 nm or 13.5 nm) can be used to form smaller features on the substrate.

[0005] In the case of an EUV lithography apparatus, as mentioned, the patterning device is typically protected by a surface film. Before applying the surface film, the surface film needs to undergo an inspection or checking process to evaluate whether it meets the specifications.

[0006] In a known arrangement, such an inspection process can be quite time-consuming and may not have the required accuracy. Summary of the Invention

[0007] An object of the present invention is to provide an inspection device for inspecting an object such as a surface film, thereby reducing the processing time and / or improving the accuracy. According to a first aspect of the present invention, there is provided an inspection device for inspecting an object such as a surface film for an EUV lithography apparatus, the inspection device comprising:

[0008] A vacuum chamber;

[0009] A load lock that forms an interface between the vacuum chamber and the surrounding environment;

[0010] A platform device configured to receive the object from the load lock and displace the object within the vacuum chamber;

[0011] wherein the vacuum chamber includes a first parking position and a second parking position for temporarily storing the object.

[0012] According to the first aspect of the present invention, there is also provided an inspection device for inspecting an object such as a pellicle for an EUV lithography apparatus, the inspection device comprising:

[0013] A vacuum chamber;

[0014] A first load lock that forms an interface between the vacuum chamber and the surrounding environment;

[0015] A second load lock that forms an interface between the vacuum chamber and the surrounding environment;

[0016] A platform device configured to receive the object from the first load lock and displace the object within the vacuum chamber, and configured to provide the object to the second load lock.

[0017] According to a second aspect of the present invention, there is provided an inspection device for inspecting an object such as a pellicle for an EUV lithography apparatus, the inspection device comprising:

[0018] A chamber configured to be configured in a regulated atmosphere for inspecting the object;

[0019] A load lock that forms an interface between the chamber and the surrounding environment;

[0020] A radiation beam source configured to generate a radiation beam for inspecting the object;

[0021] A radiation beam measurement system configured to measure characteristics of the radiation beam, wherein the radiation beam measurement system comprises:

[0022] A member disposed in an optical path of the radiation beam between the radiation beam source and the object, the member including a hole that allows a portion of the radiation beam to propagate to the object, and

[0023] At least one radiation sensor disposed on the member and configured to measure characteristics of the radiation beam. Description of the Drawings

[0024] Embodiments of the present invention will now be described, by way of example only, with reference to the accompanying schematic drawings, in which:

[0025] Figure 1 depicts a lithography system including a lithographic apparatus and a radiation source;

[0026] Figures 2A to 2F depicts a first embodiment of an inspection apparatus according to a first aspect of the present invention.

[0027] Figures 3A to 3C depicts a second embodiment of an inspection apparatus according to a first aspect of the present invention.

[0028] Figure 4 depicts a radiation beam measurement system as can be applied in an inspection apparatus according to the present invention.

[0029] Figure 5 depicts another radiation beam measurement system as can be applied in an inspection apparatus according to the present invention. Detailed Description

[0030] Figure 1 Shows a lithography system including a radiation source SO and a lithographic apparatus LA. The radiation source SO is configured to generate an EUV radiation beam B and supply the EUV radiation beam B to the lithographic apparatus LA. The lithographic apparatus LA includes an illumination system IL, a support structure MT configured to support a patterning device MA (e.g., a mask), a projection system PS, and a substrate table WT configured to support a substrate W.

[0031] The illumination system IL is configured to condition the EUV radiation beam B before the EUV radiation beam B is incident on the patterning device MA. Wherein, the illumination system IL may include a faceted field mirror device 10 and a faceted pupil mirror device 11. The faceted field mirror device 10 and the faceted pupil mirror device 11 together provide a desired cross-sectional shape and a desired intensity distribution for the EUV radiation beam B. As a supplement or alternative to the faceted field mirror device 10 and the faceted pupil mirror device 11, the illumination system IL may include other mirrors or devices.

[0032] After being so adjusted, the EUV radiation beam B interacts with the patterning device MA. As a result of this interaction, a patterned EUV radiation beam B' is produced. The projection system PS is configured to project the patterned EUV radiation beam B' onto a substrate W. To this end, the projection system PS may include a plurality of mirrors 13, 14 configured to project the patterned EUV radiation beam B' onto a substrate W held by a substrate table WT. The projection system PS may apply a reduction factor to the patterned EUV radiation beam B', thereby forming an image having features smaller than the corresponding features on the patterning device MA. For example, a reduction factor of 4 or 8 may be applied. Although the projection system PS is illustrated in Figure 1 as having only two mirrors 13, 14, the projection system PS may include a different number of mirrors (e.g., six or eight mirrors). The substrate W may include a previously formed pattern. In this case, the lithographic apparatus LA aligns the image formed by the patterned EUV radiation beam B' with the pattern previously formed on the substrate W.

[0033] A relatively high vacuum, i.e., a small amount of gas (e.g., hydrogen) at a pressure far below atmospheric pressure, may be provided in the radiation source SO, the illumination system IL, and / or the projection system PS.

[0034] The radiation source SO may be a laser-produced plasma (LPP) source, a discharge-produced plasma (DPP) source, a free electron laser (FEL), or any other radiation source capable of producing EUV radiation.

[0035] The present invention relates to the manufacture of a device or a component for use in a device. The device may be a lithographic apparatus, such as an extreme ultraviolet (EUV) lithographic apparatus that may be used to manufacture integrated circuit chips. The component may be, for example, a diaphragm or a pellicle for use in the device.

[0036] During the production of components, it may be necessary to test the components to ensure that they meet certain criteria. Some tests can be performed in a specific environment, such as a vacuum environment. This can be provided in a vacuum chamber. Of course, it should be understood that other processing, measurement, or operation of the components can also be performed in the vacuum chamber. To maintain a vacuum environment in the vacuum chamber, a fore chamber (also known as a load lock) can be provided. Components can be inserted into the load lock at ambient pressure. Subsequently, the load lock is sealed and air is pumped out until a vacuum condition matching the vacuum condition of the vacuum chamber prevails in the load lock. Subsequently, the load lock is opened to the vacuum chamber and then the components can be moved from the load lock to the vacuum chamber ready for performing tests or other processes. When the components are to be removed from the vacuum chamber, the process is reversed. In other words, the components are transferred to the load lock in vacuum and the load lock is closed off from the vacuum chamber. Subsequently, the ambient pressure is restored to the load lock by pumping air into the space inside the load lock. Once the ambient pressure is reached, the load lock can be opened and the components can be removed.

[0037] In the case of sensitive and / or precision components (such as pellicles for EUV equipment), the pumping and venting times can be on the order of several hours in order to maintain the mechanical integrity of the components by maintaining a low pressure differential and to reduce the risk of contamination by maintaining a low gas flow rate. This can be significantly greater than the time taken to test the components in the vacuum chamber, for example up to twice as long.

[0038] The present invention discloses two solutions to the above problems. In a first embodiment, the present invention provides an inspection apparatus for inspecting an object or component, such as a pellicle, used in an EUV lithography apparatus.

[0039] According to the first embodiment, the inspection apparatus includes:

[0040] a vacuum chamber;

[0041] a load lock that forms an interface between the vacuum chamber and the surrounding environment;

[0042] a platform device configured to receive components from the load lock and displace an object within the vacuum chamber.

[0043] In addition, according to the first embodiment, in order to reduce the total manufacturing and / or testing time, or more specifically, to increase the throughput of components, it is proposed to use a portion of the vacuum chamber for storing components such that a loading and / or unloading phase can be performed on a first component while a second component is being tested.

[0044] In particular, in an embodiment of the present invention, the vacuum chamber of the inspection device includes a first parking position and a second parking position. According to the present invention, a parking position refers to a position or part where a component can be temporarily stored.

[0045] According to a first embodiment of the present invention, it is thus proposed to provide two parking positions inside the vacuum chamber. As will be illustrated below, applying two parking positions inside the vacuum chamber enables operating the load lock when a first component is present inside the load lock, and such operation may include pumping air out of the load lock or pumping air into the load lock while performing the process (such as inspecting a second component arranged inside the vacuum chamber). The possible sequence of such a process is further illustrated below. Figures 2A to 2F illustrates a possible sequence of such a process. Figures 2A to 2F A plan view of an inspection device 100 according to the present invention is schematically shown. In the illustrated embodiment, the inspection device includes a vacuum chamber 110, a load lock 120, and a platform device 130. Thus, the vacuum chamber 110 includes two parking positions 140.1 and 140.2, also denoted as PP1 and PP2.

[0046] In an embodiment, a load lock such as the load lock 120 can be regarded as an interface between a first atmosphere and a second atmosphere (such as between an ambient atmosphere or ambient and a vacuum environment). Such a load lock may include, for example, a first door (dashed line) 120.1, a second door 120.2, and a load lock chamber 120.3. The first door 120.1 is configured to separate the surrounding environment from the load lock chamber 120.3, and the second door 120.2 is configured to separate the vacuum chamber 110 from the load lock chamber 120.3. Generally, the load lock chamber 120.3 should be large enough to accommodate components, such as product A or product B.

[0047] Figure 2A Shows the inspection device 100 during a first process step, in which a first component (product A, such as a watch film) undergoes measurement or inspection in the vacuum chamber while a second component (product B) is loaded into the load lock. In the illustrated embodiment, the platform device 130 includes an X platform 130.1 configured to displace the product (i.e., the product A in the above) mounted to the platform device in the X direction, and a Y platform configured to displace the product A in the Y direction. Figure 2A the product A in the above) in the Y direction.

[0048] Isolate the load lock from the vacuum chamber enclosure; i.e., close door 120.2. After loading product B into the load lock (specifically, the load lock chamber 120.3), the first door 120.1 can also be closed, and air can be pumped out of the load lock chamber 120.3. This process of pumping out air can be carried out while measuring product A.

[0049] In Figure 2B In the second step shown in Figure 2B , move product A to the first storage area (parking position 1, PP1, 140.1). In an embodiment, this step can be performed, for example, by the platform device 130 (specifically the X-platform 130.1 and the Y-platform 130.2). In an embodiment, the platform device 130 can include, for example, one or more linear motors, such as a linear motor that displaces the object (such as the film) in the X direction and a linear motor that displaces the object in the Y direction.

[0050] In Figure 2C In the third step shown in Figure 2C , open the load lock door 120.2 leading to the vacuum chamber 110, retrieve product B from the load lock 120, and transfer it into the vacuum chamber 110 while product A remains in the first storage area 140.1.

[0051] In Figure 2D In the fourth step shown in Figure 2D , move product B to the second storage area (parking position 2, PP2, 140.2). In the embodiment shown, the load lock 120 includes a transfer mechanism 150 configured to transfer an object from the load lock 120 to the platform device 130 and vice versa. It can be noted that such a transfer mechanism can also be located on the platform device or at other positions in the vacuum chamber 110. In an embodiment, the end portion 150.1 of the transfer mechanism can be configured to hold the object and lift and / or lower the object.

[0052] In Figure 2E In the fifth step shown in Figure 2E , product A returns from the first storage area 140.1 to the load lock 120. In this regard, it can be noted that due to the application of two parking positions PP1 and PP2, this transfer can be performed by the platform device 130. Thus, due to the use of two parking positions, there is no need to install or use an additional transfer robot in the vacuum chamber.

[0053] Finally, in Figure 2FIn the sixth step shown in, seal the load lock 120, i.e., close the load lock door 120.2, and return to the ambient conditions when testing product B. Once the load lock 120 returns to the ambient conditions, product A can be unloaded.

[0054] By using the first and second storage areas located in the vacuum chamber, it is possible to reduce the measurement cycle time to approximately 1 / 1.5, i.e., a reduction of (1.5 - 1) / 1.5. This is because, in particular, the second component can be loaded or unloaded while the first component is undergoing measurement. In such a configuration, the loading / unloading time of one component overlaps with the measurement process time of the other component, thus improving the throughput of the component to be tested / measured and reducing the total processing time.

[0055] According to a second embodiment of the first aspect of the present invention, a second load lock can be used. In such a configuration, loading and unloading can occur simultaneously. For example, while measuring the first component, the second component can be unloaded after the aforementioned measurement and the third component can be loaded before the subsequent measurement. Using this process, the measurement cycle time can be reduced to up to 1 / 2. Since the throughput is significantly increased, this can also reduce the amount of manufacturing equipment and / or the clean room space required to manufacture the components.

[0056] In Figures 3A to 3C illustrates a possible sequence of steps for using a vacuum chamber with two load locks. Figures 3A to 3C Schematically depicts a cross-sectional view in the vertical plane (XZ-plane).

[0057] Figure 3A Shows an inspection device 200 according to an embodiment of the present invention. In the embodiment shown, the inspection device includes a vacuum chamber 210 having two load locks 1 and 2 (also indicated by reference numerals 222 and 224). Three components (products A, B, and C), such as objects such as pellicles for EUV lithography equipment, are positioned in the vacuum chamber 210 and the load locks 222 and 224. The load locks 222 and 224 can, for example, have a structure similar to the load lock 120 described above, i.e., including a first door and a second door and a load lock chamber as described above. In the embodiment shown, product A has been processed in the vacuum chamber 210 and has been moved to the load lock 224. The load lock 224 has been sealed off from the vacuum chamber 210 and is being returned to the ambient conditions for unloading product A. Product B has been loaded from the load lock 222 into the vacuum chamber 210 for processing. The load lock 222 has then been sealed off from the vacuum chamber and returned to the ambient conditions to enable product C to be loaded into the load lock 1. Figures 3A to 3CFurther schematically shown is a platform device 230 disposed inside the vacuum chamber 210. In the illustrated embodiment, the load locks 222 and 224 further include transfer mechanisms 252 and 254 for transferring objects from the load lock chambers to the vacuum chamber and vice versa.

[0058] Subsequently, when measuring and / or processing product B in the vacuum chamber, the load lock 1, 222 containing product C can be brought from ambient pressure into the vacuum condition. Subsequently, product A is unloaded from the load lock 2, 224, and then the load lock 2, 224 returns to the vacuum condition ready to receive product B. Subsequently, the door 224.2 separating the load lock 224 from the vacuum chamber 210 is opened and after completion of the measurement process, product B is transferred to the load lock 224. Figure 3B This situation is illustrated in.

[0059] Meanwhile, the load lock 222 continues to be brought into the vacuum condition to allow product C to be transferred to the vacuum chamber.

[0060] Once the load lock 222 has been brought into the vacuum condition, the door 222.2 separating the load lock 222 from the vacuum chamber 210 is opened and product C is transferred to the vacuum chamber 210. At the same time, the load lock 224 is sealed off from the vacuum chamber 210 and can be vented to ambient pressure, so that product B can be unloaded. Finally, the measurement and / or processing of product C can be carried out while the next component is loaded into the load lock 222. These steps are schematically shown in Figure 3C In.

[0061] According to the invention, the inspection device may further include a radiation source for inspecting the object and a detector for receiving radiation emitted, reflected or transmitted from the object, in order to perform an inspection or quality assessment process. In the context of the present invention, such a radiation source may include any suitable form of radiation, such as electromagnetic radiation or a particle beam such as an electron beam or an ion beam.

[0062] According to a second aspect of the invention, there is provided an inspection device for inspecting an object such as a pellicle.

[0063] Some lithographic apparatuses include a pellicle attached to a patterned mask. The pellicle is a transmissive film spaced a few millimeters from the pattern of the mask. Contamination particles received on the pellicle are in the far field with respect to the pattern of the mask and thus have no significant effect on the quality of the image projected by the lithographic apparatus onto the substrate. If there is no pellicle, the contamination particles can be on the pattern of the mask and may thus obscure a part of the pattern, thereby preventing the pattern from being correctly projected onto the substrate.

[0064] An inspection device, also known as a pellicle inspection system, can be configured to determine optical properties of the pellicle, such as reflectivity and / or transmittance, in order to determine whether the pellicle has a high enough quality for use in a lithographic apparatus. Such pellicle inspection or inspection can involve directing a measurement radiation beam towards the pellicle and using radiation sensors to detect the intensity of the measurement radiation beam before and after the measurement radiation beam has interacted with the pellicle. This enables comparison of the characteristics of the measurement radiation beam before and after it has interacted with the pellicle, thereby enabling determination of how the pellicle affects the measurement radiation beam and whether the pellicle has a high enough quality for use in a lithographic apparatus.

[0065] A known pellicle inspection system uses two radiation sensors to detect the intensity of the measurement radiation beam before the measurement radiation beam has interacted with the pellicle. A first portion of the measurement radiation beam is directed along a main measurement path, where the measurement radiation beam interacts with the pellicle. A second portion of the measurement radiation beam is directed to the radiation sensors. Thus, the two radiation sensors are positioned on different optical paths and / or receive incident radiation at different angles to the main measurement path. The optical paths can be different from each other. The difference between the different optical paths can vary over time. For example, optical components (such as lenses and / or mirrors) in the different optical paths can be degraded differently, temperature and subsequent thermal deformation can change the vacuum or gas in the optical paths, etc. Due to the different optical paths, there are random differences between the first and second portions of the measurement radiation beam and thus the accuracy of the known pellicle inspection system is reduced. Known methods of improving the accuracy of the known pellicle inspection system involve the use of beam splitters and / or grazing incidence mirrors. However, such optical components reduce the intensity of the radiation, which in turn adversely affects the accuracy of the system. The inspection device according to the second aspect of the present invention provides an alternative way to measure a radiation beam as applied to inspect or check a pellicle.

[0066] Figure 4 A top view ( Figure 4 left side) and a side view ( Figure 4 right side) of a novel radiation beam measurement system (also known as a pellicle inspection system) as applied to an inspection device according to the second aspect of the present invention are schematically shown.

[0067] The inspection device according to the second aspect of the present invention can for example comprise:

[0068] a chamber configured to be arranged in a regulated atmosphere for inspecting the object;

[0069] a load lock forming an interface between the chamber and the surrounding environment;

[0070] A radiation beam source configured to generate a radiation beam for inspecting the object;

[0071] A radiation beam measurement system configured to measure characteristics of the radiation beam.

[0072] In an embodiment, the conditioned atmosphere can be, for example, a vacuum environment. Depending on the type of radiation used for inspection or verification, other types of conditioned atmospheres or environments can also be considered.

[0073] In the context of the present invention, any suitable type of radiation can be used as the radiation beam source for inspecting or verifying the surface film.

[0074] According to a second aspect of the present invention, the radiation beam measurement system as applied to the inspection device or surface film verification system further comprises:

[0075] A member disposed in the optical path of the radiation beam between the radiation beam source and the object, the member including a hole that allows a portion of the radiation beam to propagate to the object, and

[0076] At least one radiation sensor disposed on the member and configured to measure characteristics of the radiation beam.

[0077] In an embodiment, the radiation beam measurement system includes a plurality of radiation sensors (e.g., four or eight radiation sensors) disposed on the member, the member being disposed in the optical path of the radiation beam between the radiation beam source and the object, i.e., downstream of the radiation beam source and upstream of the object. In Figure 4 an example, the member 400 of the radiation beam measurement system is equipped with eight radiation sensors, reference numerals 1 to 8. In the embodiment as shown, the member 400 includes a generally rectangular hole 410. The eight radiation sensors 1 to 8 are disposed on two opposite sides of the hole 410 or along the two opposite sides. In Figure 4 the left side in, reference numeral 412 refers to the width of the radiation beam after passing through the hole 410, and reference numeral 414 refers to the width of the radiation beam incident on the member 400. In an embodiment, the radiation beam measurement system includes at least one radiation sensor configured to measure a characteristic (e.g., the intensity of the radiation beam (i.e., the incident radiation beam as depicted)).

[0078] A relatively large number of radiation sensors may preferably be used because any noise present in the measurements performed by the radiation beam measurement system can be reduced by averaging the results of the measurements performed by each radiation sensor. The radiation sensors may be configured to detect EUV radiation. The radiation sensors may for example comprise a photodiode and / or a camera, such as a charge-coupled device. The radiation beam measurement system may be configured to determine the spatial intensity distribution of the incident radiation beam. The radiation sensors may detect the measurement radiation beam close to the central axis of the optical path of the radiation beam to be measured.

[0079] In an embodiment, the inspection system or pellicle inspection system may comprise a spectral purity filter (SPF) 422 and a detector 430, such as a charge-coupled device (CCD). In the embodiment as shown, the detector 430 is arranged downstream of the object (i.e. the pellicle 440 to be inspected or checked). In such an embodiment, the detector thus receives the radiation transmitted through the object 440. Generally, the inspection apparatus according to the second aspect of the invention may be configured to receive any type of radiation caused by the interaction of the radiation beam with the object 440. Such radiation may for example comprise radiation emitted by the object, or radiation reflected by the object, or radiation transmitted or transmitted through the object.

[0080] The spectral purity filter 422 may be configured to filter the incident radiation beam 450 before it is incident on the pellicle 440. Thus, the SPF 422 may be arranged upstream of the pellicle 440. The CCD, typically the detector 430, may be arranged to detect the radiation beam 450 after the radiation beam 450 has interacted with the pellicle 440. The radiation sensors 1 to 8 of the radiation beam measurement system may be configured to detect the radiation beam 450 after the radiation beam has interacted with the spectral purity filter 422 and before the radiation beam has interacted with the CCD 430. A comparison between the measurements performed by the radiation beam measurement system and the measurements performed by the CCD of the pellicle inspection system may be used to determine what effect the pellicle 440 has on the radiation beam, and thereby determine whether the pellicle 440 is suitable for use in a lithographic apparatus.

[0081] The spectral purity filter 422 can be held in place by a support. In the embodiment shown, the spectral purity filter 422 is mounted to the member 400 via the support 420. In the embodiment shown, the member 400 includes a hole 410 through which at least a portion of the radiation beam (which may be referred to as the first portion of the radiation beam) passes before the radiation beam impinges on the pellicle. The radiation sensors 1 to 8 of the radiation beam measurement system can be mounted on the member 400. The edges of the radiation sensors can be generally aligned with the edges of the holes of the member 400. The surface of the member 400 on which the radiation beam measurement system is mounted and the radiation sensors of the radiation beam measurement system are used to block some of the incident radiation beam 450 (which may be referred to as the second portion of the incident radiation beam). Since the edges of the radiation sensors are generally aligned with the edges of the holes 410 of the member 400, the radiation beam measurement system can measure the characteristics of the radiation beam 450 as close as possible to the central axis of the radiation beam without affecting the portion of the radiation beam that interacts with the pellicle (and which can be detected by the CCD 430 of the inspection device or pellicle inspection system). The radiation beam measurement system can be the final optical component that interacts with the radiation beam before the radiation beam impinges on the pellicle 440. Thus, in the measurements performed by the radiation beam measurement system, the effects of all other optical components in the optical path of the radiation beam are included and taken into account. Therefore, compared with known radiation beam measurement systems, changes in the optical path of the radiation beam have a smaller impact on the accuracy of the novel radiation beam measurement system.

[0082] The radiation beam measurement system is advantageously capable of monitoring the characteristics (e.g., energy, spatial intensity distribution, dose, etc.) of the incident radiation beam in situ without significantly affecting the radiation beam. This can improve the accuracy of subsequent measurements performed using the radiation beam after the radiation beam has interacted with the pellicle. The radiation beam measurement system allows for setup calibration using the CCD 430 as a reference. For example, when the pellicle 440 is not disposed between the support and the CCD 430, both the radiation sensors 1 to 8 of the radiation beam measurement system and the CCD 430 can be used to determine the characteristics of the incident radiation beam 450. The direct measurement results of the CCD 430 from the first portion of the radiation beam can be used to calibrate the indirect measurement results of the radiation sensors 1 to 8 from the radiation beam measurement system. The radiation beam measurement system is compact and easy to install and use. The radiation beam measurement system can be capable of reconstructing the spatial intensity distribution of the radiation by, for example, using a combination of known positions of the radiation sensors, performing reference measurements, comparing the measurements with a database of information about the characteristics of the radiation beam, and a fitting algorithm. The radiation beam measurement system may be cheaper to install and / or operate than known radiation beam measurement systems.

[0083] In such Figure 4 In the embodiment shown in FIG. 4 , the radiation sensors 1 to 8 are arranged along two opposite sides of the hole 410, the opposite sides extending in the Y direction. It may also be advantageous to include or arrange radiation sensors along one or both sides extending in the X direction. Such an embodiment is schematically shown in FIG. Figure 5 In. Except Figure 4 In addition to the features shown in Figure 5 A further pair of radiation sensors 20, 21 is schematically shown, which are arranged on or along two opposite sides of an aperture 410 extending in the X-direction.

[0084] In an embodiment of the invention, at least one radiation sensor is arranged along the circumference of the aperture 410 of the member 400 of the radiation beam measurement system. In an embodiment, at least one radiation sensor is arranged along each side of the aperture 410 of the member 400.

[0085] In an embodiment, the inspection apparatus according to the present invention may advantageously be used to measure the transmission and / or reflection properties of an object such as a pellicle, in particular an EUV pellicle. In such an embodiment, the inspection apparatus may thus be referred to as an EUV pellicle transmission and / or reflection measurement tool. In such an embodiment, one or two properties as measured in such a tool are:

[0086] a) The EUV radiation transmittance through the diaphragm or pellicle, i.e., the percentage of EUV radiation (i.e., the EUV radiation that is transmitted through without being absorbed by the diaphragm or pellicle, and / or the EUV radiation reflected by the diaphragm) relative to the total radiation, and / or

[0087] b) The EUV radiation reflected by the diaphragm or pellicle, i.e., the percentage of the EUV radiation reflected back by the diaphragm or pellicle.

[0088] It can also be indicated that a portion of the EUV radiation can be absorbed by the diaphragm or pellicle. By measuring both the reflected and transmitted EUV radiation and combining the information on the total EUV radiation incident on the diaphragm or pellicle, the relationships between the three radiation components (i.e., the reflected radiation component, the absorbed radiation component, and the transmitted radiation component) can be determined. The reflection and transmission properties can be measured, for example, using a radiation detector such as a CCD camera, such as the CCD430 shown above. In particular, as Figure 4 and Figure 5 shown, the CCD camera can be arranged in the optical path of the transmitted EUV radiation. Similarly, to determine the amount of reflected EUV radiation, the CCD camera can be arranged in the optical path of the reflected EUV radiation. Such a camera can be referred to, for example, as a T-CCD (transmission) and an R-CCD (reflection).

[0089] The present invention can also be described in terms of the following:

[0090] Aspect 1: An inspection apparatus for inspecting an object such as a pellicle for an EUV lithography apparatus, the inspection apparatus comprising:

[0091] A vacuum chamber;

[0092] A load lock that forms an interface between the vacuum chamber and the surrounding environment;

[0093] A platform device configured to receive the object from the load lock and displace the object within the vacuum chamber;

[0094] wherein the vacuum chamber includes a first parking position and a second parking position for temporarily storing the object.

[0095] Aspect 2: The inspection apparatus according to aspect 1, further comprising a transfer mechanism configured to transfer the object from the load lock to the platform device and to transfer the object from the platform device to the load lock.

[0096] Aspect 3: The inspection apparatus according to aspect 2, wherein the transfer mechanism is at least partially arranged within the load lock.

[0097] Aspect 4: The inspection apparatus according to Aspect 2, wherein the transfer mechanism is mounted to the platform apparatus.

[0098] Aspect 5: The inspection apparatus according to any one of the preceding aspects, wherein the load lock includes a first door, a second door, and a load lock chamber, the first door being configured to separate the surrounding environment from the load lock chamber, and the second door being configured to separate the vacuum chamber from the load lock chamber.

[0099] Aspect 6: The inspection apparatus according to Aspect 1, wherein the platform apparatus is configured to transfer an object from the platform apparatus to the first parking position and to transfer an object from the first parking position to the platform apparatus, and wherein the platform apparatus is configured to transfer an object from the platform apparatus to the second parking position and to transfer an object from the second parking position to the platform apparatus.

[0100] Aspect 7: The inspection apparatus according to any one of the preceding aspects, wherein the platform apparatus includes a holder for holding the object.

[0101] Aspect 8: An inspection apparatus for inspecting an object such as a pellicle for an EUV lithography apparatus, the inspection apparatus comprising:

[0102] A vacuum chamber;

[0103] A first load lock that forms an interface between the vacuum chamber and the surrounding environment;

[0104] A second load lock that forms an interface between the vacuum chamber and the surrounding environment;

[0105] A platform apparatus configured to receive the object from the first load lock and displace the object within the vacuum chamber, and configured to provide the object to the second load lock.

[0106] Aspect 9: An inspection apparatus for inspecting an object such as a pellicle for an EUV lithography apparatus, the inspection apparatus comprising:

[0107] A chamber configured to be configured in a regulated atmosphere for inspecting the object;

[0108] A load lock that forms an interface between the chamber and the surrounding environment;

[0109] A radiation beam source configured to generate a radiation beam for inspecting the object;

[0110] A radiation beam measurement system configured to measure characteristics of the radiation beam, wherein the radiation beam measurement system comprises:

[0111] a member disposed in an optical path of the radiation beam between the radiation beam source and the object, the member including an aperture that allows a portion of the radiation beam to propagate to the object, and

[0112] at least one radiation sensor disposed on the member and configured to measure characteristics of the radiation beam.

[0113] Aspect 10: The inspection device according to aspect 9, wherein the at least one radiation sensor is arranged along the circumference of the aperture.

[0114] Aspect 11: The inspection device according to aspect 9 or 10, wherein the aperture has a substantially rectangular shape.

[0115] Aspect 12: The inspection device according to aspect 11, wherein the radiation beam measurement system includes radiation sensors along at least two sides of the aperture.

[0116] Aspect 13: The inspection device according to aspect 11 or 12, wherein the radiation beam measurement system includes at least one radiation sensor along each side of the aperture.

[0117] Aspect 14: The inspection device according to any one of aspects 9 to 13, wherein the radiation beam measurement system further includes a spectral purity filter disposed upstream of the member in the optical path.

[0118] Aspect 15: The inspection device according to aspect 14, wherein the spectral purity filter is mounted to the member.

[0119] Aspect 16: The inspection device according to aspect 14 or 15, wherein the at least one radiation sensor is disposed downstream of the spectral purity filter.

[0120] Aspect 17: The inspection device according to any one of aspects 9 to 16, further comprising a detector configured to receive radiation caused by an interaction of the radiation beam with the object.

[0121] Aspect 18: The inspection device according to aspect 17, wherein the radiation includes radiation transmitted by the object.

[0122] Aspect 19: The inspection device according to aspect 18, wherein the detector is disposed downstream of the object.

[0123] Aspect 20: The inspection apparatus according to any one of aspects 17 to 19, wherein the detector includes a CCD.

[0124] Aspect 21: An EUV pellicle transmission measurement tool, comprising the inspection apparatus according to any one of aspects 9 to 20.

[0125] Aspect 22: An EUV pellicle transmission and reflection measurement tool, comprising the inspection apparatus according to any one of aspects 9 to 20.

[0126] Although specific reference may be made herein to the use of lithographic apparatus in IC manufacture, it should be understood that the lithographic apparatus described herein may have other applications. Other possible applications include the manufacture of integrated optical systems, the guidance and detection of magnetic domain memories, flat panel displays, liquid crystal displays (LCDs), thin film magnetic heads, and the like.

[0127] Although embodiments of the present application may be described in detail herein in the context of a lithographic apparatus, the embodiments of the present application may be used in other apparatuses. The embodiments of the present application may form part of a mask inspection apparatus, a metrology apparatus, or any apparatus for measuring or processing an object such as a wafer (or other substrate) or a mask (or other patterning device). These apparatuses are commonly referred to as lithographic tools. Such lithographic tools may use vacuum conditions or ambient (non-vacuum) conditions.

[0128] Although detailed reference has been made herein to the use of embodiments of the present application in the context of optical lithography, it should be understood that, where the context allows, the present application is not limited to optical lithography and may be used in other applications, such as imprint lithography.

[0129] Where the context allows, embodiments of the present disclosure may be implemented in hardware, firmware, software, or any combination thereof. Embodiments of the present disclosure may also be implemented as instructions stored on a machine-readable medium, which may be read and executed by one or more processors. The machine-readable medium may include any mechanism for storing or transmitting information in a form readable by a machine, such as a computing device. For example, the machine-readable medium may include read-only memory (ROM); random access memory (RAM); magnetic disk storage media; optical storage media; flash memory devices; electrical, optical, acoustic, or other forms of propagated signals (such as carrier waves, infrared signals, digital signals, etc.); and other media. Additionally, firmware, software, routines, instructions may be described herein as performing certain actions. However, it should be understood that these descriptions are for convenience only and that these actions are actually caused by a computing device, a processor, a controller, or other device executing the firmware, software, routines, instructions, etc., and doing so may cause an actuator or other device to interact with the physical world.

[0130] Although specific embodiments of the present invention have been described above, it should be understood that the present invention can be practiced in a manner different from that described above. The foregoing description is intended to be illustrative rather than restrictive. Thus, those skilled in the art will appreciate that the described present invention can be modified without departing from the scope of the claims set forth below.

Claims

1. An inspection device for inspecting an object, the inspection device comprises: a chamber configured to inspect an object in the chamber; a load lock that forms an interface between the chamber and the surrounding environment; a radiation beam measurement system configured to measure characteristics related to a radiation beam used to inspect the object to determine: a) the EUV radiation transmittance through the object, where the EUV radiation transmittance is the percentage of EUV radiation that passes through the object without being absorbed by the object relative to the total radiation, and / or b) the EUV radiation reflected by the object, where the reflected EUV radiation is the percentage of EUV radiation reflected back by the object.

2. The inspection device according to claim 1, further comprising a detector configured to detect the radiation beam after the radiation beam has interacted with the object.

3. The inspection device according to claim 1, wherein, the measured characteristic is a characteristic of the radiation emitted by the object.

4. The inspection device according to claim 1, further comprising a spectral purity filter and a detector, the spectral purity filter being arranged upstream of the object and configured to filter the radiation beam before the radiation beam is incident on the object, the detector being configured to detect the radiation beam after the radiation beam has interacted with the object, and wherein the measurement system is arranged to detect the radiation beam after the radiation beam has interacted with the spectral purity filter and before the radiation beam has interacted with the detector.

5. The inspection device according to claim 1, wherein, the radiation beam measurement system is configured to measure the characteristics of the radiation beam as close as possible to the central axis of the radiation beam without affecting the part of the radiation beam that interacts with the object.

6. An inspection device for inspecting an object, the inspection device comprises: a chamber configured to inspect an object in the chamber; a load lock that forms an interface between the chamber and the surrounding environment; a radiation beam measurement system configured to measure the characteristics of a radiation beam used to inspect the object, the radiation beam measurement system including a detector configured to receive radiation emitted, reflected or transmitted by the object and further configured to measure the characteristics of the radiation beam along the path of the incident radiation beam towards the object.

7. The inspection device according to claim 6, wherein, the load lock comprises: a first load lock that forms an interface between the vacuum chamber and the surrounding environment; a second load lock that forms an interface between the vacuum chamber and the surrounding environment; and a platform device configured to receive the object from the first load lock and displace the object within the vacuum chamber and configured to provide the object to the second load lock.

8. The inspection device according to claim 6, wherein, The detector includes at least one radiation sensor configured to detect EUV radiation and measure characteristics of the incident radiation beam.

9. The inspection apparatus according to claim 8, wherein, the at least one radiation sensor is configured to determine the energy, dose, or spatial intensity distribution of the incident radiation beam.

10. The inspection apparatus according to claim 8, wherein, the at least one radiation sensor is configured to detect the incident radiation beam close to a central axis of an optical path of the incident radiation beam.

11. The inspection apparatus according to claim 6, further comprising a spectral purity filter, the spectral purity filter being arranged in an optical path of the radiation beam and being arranged upstream of the object in the optical path.

12. The inspection apparatus according to claim 6, wherein, the radiation beam measurement system is configured to determine EUV reflectivity and / or EUV transmittance of the object.

13. An EUV transmission and / or reflection measurement tool for inspecting and / or verifying a film used in EUV lithography, the measurement tool being configured to determine both EUV radiation transmittance through the film and EUV radiation reflected by the film, the EUV transmission and reflection measurement tool comprises: a chamber configured to provide a conditioned environment for the film; a load lock that forms an interface between the chamber and the surrounding environment; a radiation beam source configured to generate an EUV radiation beam for inspecting and / or verifying the film; optical components in an optical path of the EUV radiation beam, the optical components being arranged to interact with the EUV radiation beam; and a radiation beam measurement system configured to in-situ monitor one or more characteristics before and after the EUV radiation beam has interacted with the film by measuring reflected EUV radiation and transmitted EUV radiation, in combination with information about total EUV radiation towards the film.

14. The measurement tool according to claim 13, wherein, the monitored characteristics are selected from one or more of energy, radiation beam intensity, spatial intensity distribution, and dose.

15. The measurement tool according to claim 13 or 14, wherein, the measurement tool monitors the radiation beam intensity for reconstructing the spatial intensity distribution of the radiation.

16. The measurement tool according to claim 15, wherein, one or more of the following are used to reconstruct the spatial intensity distribution: combinations of known positions of the radiation sensors, performing reference measurements, comparing the measurements with a database of information about characteristics of the radiation beam, and fitting algorithms.

17. The measurement tool according to claim 13 or 14, wherein, the film is a pellicle or a spectral filter.

18. The measurement tool according to claim 13 or 14, wherein, the EUV source is an LPP EUV source.

19. The measuring tool according to claim 13 or 14 further comprises a spectral purity filter and a detector. The spectral purity filter is arranged upstream of the membrane and configured to filter the radiation beam before the radiation beam is incident on the membrane. The detector is configured to detect the radiation beam after the radiation beam has interacted with the membrane, and wherein the measuring system is arranged to detect the radiation beam after the radiation beam has interacted with the spectral purity filter and before the radiation beam has interacted with the detector.

20. The measuring tool according to claim 13 or 14, wherein, the radiation beam measuring system is configured to measure the characteristics of the radiation beam as close as possible to the central axis of the radiation beam without affecting the part of the radiation beam that interacts with the membrane.

21. An EUV transmission and / or reflection measuring tool for inspecting and / or verifying an object used in EUV lithography, the measuring tool being configured to determine both the EUV radiation transmittance through the object and the EUV radiation reflected by the object, the EUV transmission and reflection measuring tool comprises: a chamber configured to provide a regulated environment for inspecting the object in the chamber; a load lock that forms an interface between the chamber and the surrounding environment; a radiation beam source configured to generate an EUV radiation beam for inspecting and / or verifying the object; optical components in the optical path of the EUV radiation beam, the optical components being arranged to interact with the EUV radiation beam; and a radiation beam measuring system configured to in-situ monitor one or more characteristics before and after the EUV radiation beam has interacted with the object by measuring the reflected EUV radiation and the transmitted EUV radiation and combining information about the total EUV radiation towards the object.

22. The measuring tool according to claim 21, wherein, the radiation beam measuring system is configured to measure the characteristics of the radiation beam for inspecting the object, the radiation beam measuring system including a detector configured to receive the radiation emitted, reflected or transmitted from the object and further configured to measure the characteristics of the radiation beam along the path of the incident radiation beam towards the object.

23. The measuring tool according to claim 21 or 22, wherein, the load lock comprises: a first load lock that forms an interface between the chamber and the surrounding environment; a second load lock that forms an interface between the chamber and the surrounding environment; and a platform device configured to receive the object from the first load lock and displace the object within the chamber and configured to provide the object to the second load lock.

24. The measuring tool according to claim 22, wherein, the detector includes at least one radiation sensor configured to detect EUV radiation and measure the characteristics of the incident radiation beam.

25. The measuring tool according to claim 24, wherein, the at least one radiation sensor is configured to determine the energy, dose or spatial intensity distribution of the incident radiation beam.

26. The measuring tool according to claim 24, wherein, the at least one radiation sensor is configured to detect the incident radiation beam close to the central axis of the optical path of the incident radiation beam.

27. The measuring tool according to claim 21, wherein, further comprising a spectral purity filter, the spectral purity filter being arranged in the optical path of the radiation beam and being arranged upstream of the object in the optical path.

28. The measuring tool according to claim 21 or 22, wherein, the object for EUV lithography is one of a film, a surface film, a spectral filter, a mask, a surface film-mask assembly, a sensor deposited on the surface of a component from a lithography tool.

29. A method for inspecting and / or characterizing EUV transmission and reflection of an object used in EUV lithography for determining the EUV radiation transmittance through the object and the EUV radiation reflected by the object, the method comprising: directing a measurement radiation beam towards the object to be inspected; and by measuring the reflected EUV radiation and the transmitted EUV radiation, and combining information about the total EUV radiation towards the object, detecting the measurement radiation beam before and after the measurement radiation has interacted with the object using a radiation sensor to provide in-situ monitoring of the characteristics of the radiation beam without significantly affecting the radiation beam.

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