Lithography equipment

Abstract

A component of a lithographic apparatus having a contaminant capture surface provided with recesses configured to capture contaminant particles and reduce specular reflection of DUV radiation. The recesses may have at least one dimension less than or equal to about 2 μm, ideally less than 1 μm.

Description

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS

[0002] This application claims priority to European application 18166991.2 filed on April 12, 2018 and to Netherlands application 2021345 filed on July 19, 2018, the entire contents of which are incorporated herein by reference. Technical Field

[0003] The present invention relates to lithographic apparatus. The present invention is particularly, but not exclusively, used in conjunction with EUV lithographic apparatus and EUV lithographic tools. Background Art

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

[0005] The wavelength of radiation used by a lithographic apparatus to project a pattern onto a substrate determines the minimum size of features that can be formed on the substrate. A lithographic apparatus using EUV radiation (i.e., electromagnetic radiation having a wavelength in the range of 4-20 nm) can be used to form smaller features on a substrate than a lithographic apparatus using DUV radiation (e.g., having a wavelength of 193 nm).

[0006] Dust or other contaminants on the patterning device in a lithographic apparatus can be particularly troublesome because dust particles or other contaminants may be imaged on each device manufactured. If the effect on the pattern produced is such that the device does not function properly, yield will be severely affected until the patterning device can be cleaned. Measures to minimize contamination in a lithographic apparatus, particularly in the vicinity of the patterning device, are very important. Summary of the invention

[0007] According to a first aspect of the invention, there is provided a component of a lithographic apparatus having a contaminant capturing surface texture provided with recesses configured to capture contaminant particles and reduce specular reflection of DUV radiation (which is a spurious component in EUV formation).

[0008] In one embodiment, the recess has at least one dimension less than or equal to about 2 μm, ideally less than 1 μm.

[0009] According to a second aspect of the present invention, there is provided a method of manufacturing a contamination trap for a lithographic apparatus, the method comprising: processing a surface of a component of the lithographic apparatus to form a recess, the recess being configured to capture contaminant particles and reduce specular reflection of DUV radiation.

[0010] According to a third aspect of the invention there is provided use of a component according to the invention in a lithographic apparatus for capturing contaminant particles and reducing specular reflection of DUV radiation. The lithographic apparatus may be an EUV lithographic apparatus.

[0011] According to a fourth aspect of the present invention, there is provided a use of a surface texture in a lithography apparatus for capturing contaminant particles and reducing specular reflection of DUV radiation, the surface texture having a plurality of recesses, the width of the recesses being less than or equal to about 2 μm and the depth being greater than or equal to about 1 μm. The lithography apparatus may be an EUV lithography apparatus. The width of the recesses may be less than 1 μm. The depth of the recesses may be greater than or equal to 10 μm.

[0012] The first, second, third and fourth aspects of the present invention enable the capture of particles having a size no smaller than the width of the recess. The size of the captured particles may be less than about 1 μm.

[0013] Features of different aspects of the invention may be combined with features of other aspects of the invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] Embodiments of the invention will now be described, by way of example only, with reference to the accompanying schematic drawings, in which:

[0015] Figure 1 is a schematic diagram of a lithography system including a lithography apparatus and a radiation source;

[0016] Figure 2 is through Figure 1 A schematic diagram of a first cross-section of an object and a masking blade on a support structure of a lithography apparatus;

[0017] Figure 3 is through Figure 1 A schematic diagram of a second cross-section of an object and a masking blade on a support structure of a lithography apparatus;

[0018] Figure 4 The first configuration is shown Figure 1 A plan view of a y mask blade and an x ​​mask blade (dashed line) of a lithography apparatus;

[0019] Figure 5 The second configuration is shown Figure 1 A plan view of a y mask blade and an x ​​mask blade (dashed line) of a lithography apparatus;

[0020] Figure 6 is an image of a surface texture that can be used in embodiments of the present invention;

[0021] Figure 7 is an image of another surface texture that may be used in embodiments of the present invention; and

[0022] Figure 8 Depicted are grooves in the surface texture of an embodiment of the present invention. DETAILED DESCRIPTION

[0023] Figure 1 is a schematic diagram of a lithography system. The lithography system comprises a radiation source SO and a lithography apparatus LA. The radiation source SO is configured to generate an extreme ultraviolet (EUV) radiation beam B. The lithography apparatus LA comprises an illumination system IL, a support structure MT configured to support a pattern forming device MA, a projection system PS and a substrate table WT configured to support a substrate W. The illumination system IL is configured to condition the radiation beam B before the radiation beam B is incident on the pattern forming device MA. The projection system is configured to project the radiation beam B (now patterned by the pattern forming device MA) onto the substrate W. The substrate W may include a previously formed pattern. In this case, the lithography apparatus aligns the patterned radiation beam B with a pattern previously formed on the substrate W.

[0024] The radiation source SO, the illumination system IL and the projection system PS may all be constructed and arranged so that they may be isolated from the external environment. A gas (e.g., hydrogen) at a pressure condition below atmospheric pressure may be provided in the radiation source SO. A vacuum may be provided in the illumination system IL and / or the projection system PS. A small amount of gas (e.g., hydrogen) at a pressure condition far below atmospheric pressure may be provided in the illumination system IL and / or the projection system PS.

[0025] Figure 1 The radiation source SO shown is of a type that may be referred to as a laser produced plasma (LPP) source. A laser 1, which may be, for example, a CO2 laser, is arranged to deposit energy into a fuel, such as tin (Sn), provided from a fuel emitter 3, by means of a laser beam 2. Although reference is made to tin in the following description, any suitable fuel may be used. The fuel may, for example, be in liquid form and may, for example, be a metal or an alloy. The fuel emitter 3 may include a nozzle configured to direct the tin, for example in the form of droplets, along a trajectory towards a plasma formation region 4. The laser beam 2 is incident on the tin at the plasma formation region 4. The deposition of laser energy into the tin generates a plasma 7 at the plasma formation region 4. During de-excitation and recombination of the ions of the plasma, radiation, including EUV radiation, is emitted from the plasma 7.

[0026] EUV radiation is collected and focused by a radiation collector 5 at near normal incidence (sometimes more generally referred to as a normal incidence radiation collector). The collector 5 may have a multilayer structure arranged to reflect EUV radiation (e.g., EUV radiation having a desired wavelength such as 13.5 nm). The collector 5 may have an elliptical configuration with two elliptical foci. As described below, the first focus may be at the plasma formation region 4, and the second focus may be at the intermediate focus 6.

[0027] In other embodiments of the laser produced plasma (LPP) source, the collector 5 may be a so-called grazing incidence collector configured to receive EUV radiation at a grazing incidence angle and to focus the EUV radiation at an intermediate focus. The grazing incidence collector may be, for example, a nested collector comprising a plurality of grazing incidence reflectors. The grazing incidence reflectors may be arranged axially symmetrically around the optical axis O.

[0028] The radiation source SO may include one or more contamination traps (not shown). For example, the contamination trap may be located between the plasma formation region 4 and the radiation collector 5. The contamination trap may be, for example, a rotating foil collector, or may be any other suitable form of contamination trap.

[0029] The laser 1 may be separated from the radiation source SO. In this case, the laser beam 2 may be transferred from the laser 1 to the radiation source SO by means of a beam delivery system (not shown), which may include, for example, suitable guide mirrors and / or beam expanders, and / or other optical devices. The laser 1 and the radiation source SO may be considered together as a radiation system.

[0030] The radiation reflected by the collector 5 forms a radiation beam B. The radiation beam B is focused at a point 6 to form an image of the plasma formation region 4, which serves as a virtual radiation source for the illumination system IL. The point 6 at which the radiation beam B is focused may be referred to as an intermediate focus. The radiation source SO is arranged such that the intermediate focus 6 is located at or near an opening 8 in an enclosure structure 9 of the radiation source.

[0031] A radiation beam B enters an illumination system IL from a radiation source SO, which is configured to condition the radiation beam. 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 the radiation beam B with a desired cross-sectional shape and a desired angular distribution. The radiation beam B passes from the illumination system IL and is incident on a patterning device MA held by a support structure MT. The patterning device MA (for example, which may be a mask) reflects and patterns the radiation beam B. In addition to or in place of 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 reflection from the patterning device MA, the patterned radiation beam B enters the projection system PS. The projection system comprises a plurality of mirrors 13, 14 configured to project the radiation beam B onto a substrate W held by a substrate table WT. The mirrors 13, 14 forming the projection system may be configured as reflecting lens elements. The projection system PS may apply a reduction factor to the radiation beam so as to form an image having features that are smaller than corresponding features on the patterning device MA. For example a reduction factor of 4 may be applied. Although in Figure 1 The projection system PS has two mirrors 13, 14, but the projection system may comprise any number of mirrors (eg six mirrors).

[0033] The lithographic apparatus may, for example, be used in a scanning mode in which the support structure (e.g. mask table) MT and the substrate table WT are scanned synchronously (i.e. dynamically exposed) while a pattern imparted to the radiation beam is projected onto the substrate W. The speed and direction of the substrate table WT relative to the support structure (e.g. mask table) MT may be determined by the demagnification and image reversal characteristics of the projection system PS. The patterned radiation beam incident on the substrate W may include a band of radiation. The band of radiation may be referred to as an exposure slit. During scanning exposure, movement of the substrate table WT and the support structure MT may cause the exposure slit to travel over an exposure field of the substrate W.

[0034] Figure 1 The radiation source SO and / or the lithographic apparatus shown may include components not shown. For example, a spectral filter may be provided in the radiation source SO. The spectral filter may be substantially transmissive for EUV radiation, but substantially block radiation of other wavelengths, such as infrared radiation.

[0035] In other embodiments of the lithography system, the radiation source SO may take other forms. For example, in alternative embodiments, the radiation source SO may include one or more free electron lasers. The one or more free electron lasers may be configured to emit EUV radiation that may be provided to one or more lithography devices.

[0036] Reference now Figures 2 to 5 A masking system according to an embodiment of the invention is described.The masking system is located in the illumination system and controls the area of ​​an object (eg patterning device MA) that is illuminated by the radiation beam.

[0037] In use, the masking system is arranged so that it can be moved into and out of the optical path of radiation between the illumination system IL and the projection system PS. Such a masking arrangement provides control of the radiation distribution in a field plane of the lithographic apparatus downstream of the apparatus. Such a field plane comprises the plane of the support structure MT (i.e. the plane of the patterning device MA) and the plane of the substrate table WT (i.e. the plane of the substrate W).

[0038] The lithographic apparatus is provided with four masking blades which define the extent of the field illuminated on the patterning device MA, as now referred to Figure 2 and 3 The illumination system IL is operable to illuminate a generally rectangular area of ​​an object disposed on the support structure MT (e.g., the pattern forming device MA). The generally rectangular area may be referred to as a slit of the illumination system IL and is defined by four masking blades. The extent of the generally rectangular area in a first direction (which may be referred to as the x-direction) is defined by a pair of x masking blades 110, 112. The extent of the generally rectangular area in a second direction (which may be referred to as the y-direction) is defined by a pair of y masking blades 114, 116.

[0039] Each masking blade 110,112,114,116 is arranged close to but slightly out of the plane of an object 118 on the support structure MT. The x-masking blades 110,112 are arranged in a first plane 120 and the y-masking blades 114,116 are arranged in a second plane 122.

[0040] Each masking blade 110, 112, 114, 116 defines one side of a rectangular field region 124 in the plane of the object 118 receiving the radiation. Each blade can be independently moved between a retracted position in which it is not disposed in the path of the radiation beam and an inserted position in which it at least partially blocks the radiation beam projected onto the object 118. By moving the masking blades 110, 112, 114, 116 into the path of the radiation beam, the radiation beam B can be truncated (in the x and / or y direction), thereby limiting the extent of the field region 124 in which the radiation beam B is received.

[0041] The x-direction may correspond to a non-scanning direction of the lithographic apparatus LA, and the y-direction may correspond to a scanning direction of the lithographic apparatus LA. That is, the object 118 may be moved in the y-direction across the field region 124 (as indicated by arrow 126) to expose a larger area of ​​the object in a single dynamic scanning exposure.

[0042] During dynamic exposure of a target area of ​​a substrate W, the target area moves through an exposure area in the plane of the substrate W, which is the portion of the substrate W onto which an exposure area 124 of an object 118 is projected by the projection system PS. As the target area of ​​the substrate W moves into the exposure area, the first mask blades 114, 116 move so that only the target area receives radiation (i.e., no portion of the substrate outside the target area is exposed). At the start of the scanning exposure, one of the y-masking blades 114, 116 is disposed in the path of the radiation beam B to act as a shield so that no portion of the substrate W receives radiation. At the end of the scanning exposure, the other of the y-masking blades 114, 116 is disposed in the path of the radiation beam B to act as a shield so that no portion of the substrate W receives radiation.

[0043] A ray of radiation beam B is shown adjacent to each masking blade 110, 112, 114, 116. It should be understood that each point in field area 124 is illuminated by radiation from a range of angles. For example, each point in field area 124 may receive a cone of radiation. A ray of radiation beam B is shown adjacent to each masking blade 110, 112, 114, 116, indicating an average direction of radiation received by the object. Figure 2 and 3 It can be seen that in this embodiment, the radiation is generally perpendicularly incident on the object 118 when projected onto the xz plane, and is generally incident on the object 118 at an angle 128 when projected onto the yz plane.

[0044] Figure 4 and 5 A plan view of the Y masking blades 114, 116 is shown, with the positions of the X masking blades 110, 112 shown in phantom. Figure 4 , four masking blades 110, 112, 114, 116 are arranged to define a generally rectangular field region 124. This may be a typical configuration of the four masking blades 110, 112, 114, 116 during exposure of a central portion of a target region (e.g., a chip on a substrate W). As described above, each x masking blade 110, 112 is operable to move in the x-direction and each y masking blade 114, 116 is operable to move in the y-direction to control the size of the field region 124. The y masking blades 114, 116 are configured so that they can be actuated from the same side of the field region 124. To achieve this, the y masking blades 114, 116 are shaped so that (although they are substantially located on the same plane 122) each y masking blade 114, 116 is provided with a plurality of y masking blades 114, 116 disposed along the same direction ( Figures 4 to 5 One or more support portions extending in the positive y direction (in the positive y direction).

[0045] exist Figure 5 In, relative to Figure 4 In the configuration shown in , one of the y masking blades 114 has been moved (in the positive y direction) so as to be disposed in the path of the radiation beam B to act as a shield. Furthermore, one of the x masking blades 110 has been moved (in the positive x direction) so as to be disposed in the path of the radiation beam B to act as a shield. Figure 5 Also shown (as a cross-hatched rectangle) is the Figure 4 The configuration of the masking blades shown corresponds to field region 124 . Figure 4 and 5 can be viewed as representing the two end positions of the nominal motion of the y-masking blade 114 and the x-masking blade 110, where Figure 4 represents a retracted position allowing exposure of the substrate W, while Figure 5 1 shows an insertion position of a shielding member for preventing the substrate W from being exposed to light.

[0046] As mentioned above, it is very necessary in a lithographic apparatus to prevent contaminants such as particulates from adhering to sensitive components of the lithographic apparatus. In particular, particles on a patterning device such as a mask are detrimental because they may be imaged onto every target portion of every substrate imaged using the patterning device. If a particle is of a size and / or position on the patterning device such that its image causes a device to malfunction when printed, the yield of the lithographic process will be severely affected. Even when a pellicle is used to prevent particles from being deposited directly on the patterning device, large particles and / or large numbers of particles can cause imaging errors and / or loss of contrast at the substrate level.

[0047] The masking blade described above may be a source of particles that may end up on the patterning device. The masking blade is a moving element and therefore there is a risk of particles being generated by friction. In addition, there is a risk that particles may be transported from elsewhere in the device and end up on the patterning device as the reticle masking blade moves across the patterning device. Furthermore, cooling gas flows near the masking blade and the patterning device may transfer particles to the patterning device.

[0048] In EUV lithography apparatus, it is also desirable to suppress the transmission of DUV radiation to the substrate, which is an undesirable or harmful component of the radiation generated by the plasma. Such DUV radiation may have a wavelength in the range of 100 nm to 300 nm. Any DUV radiation that reaches the substrate will reduce the contrast of the projected image, as the resist is sensitive to such DUV radiation as well as EUV radiation, and thus DUV radiation will reduce the process window.

[0049] Thus, the present invention provides a component that acts as a contamination trap by providing a surface treatment that produces a texture including recesses on the treated surface that both enhances particle adhesion and reduces reflectivity of DUV radiation.

[0050] In an embodiment of the present invention, at least one dimension of the recess is less than or equal to about 2 μm, ideally less than 1 μm. Desirably, the recesses are closely packed together and evenly distributed on the relevant surface. The exact shape and form of the recess is not more important than its size. Desirably, the recess depth is larger than the size of the particle to be captured, but the width is not much larger than the particle to be captured. In this way, the particles can be held in the recess by electrostatic forces such as van der Waals forces. The particles held in the recess are then less likely to transfer to the pattern forming device. In addition, the particles held in the recess cannot migrate on the surface of the component and are therefore less likely to aggregate and agglomerate. Aggregated particles are more likely to fall off moving components (such as masking blades) and are more likely to cause imaging errors.

[0051] In an embodiment of the present invention, the depth of the recess is greater than or equal to about 1 μm, and ideally greater than or equal to about 10 μm. The particle capture function of the recess increases with depth, so deeper recesses can be wider while still having the same capture effect. The depth of the recess can be less than or equal to about 500 μm. The width of the recess may taper away from the surface. The width of the recess can be greater than or equal to about 50 nm.

[0052] At the same time, the texture provided to the surface of the component reduces the reflectivity of the surface of the component to DUV radiation. The reflectivity to DUV is reduced compared to the case where no treatment is performed on the corresponding surface. In one embodiment of the present invention, the reflectivity to DUV is reduced to less than 20%. In this document, DUV radiation should be regarded as radiation in the wavelength range of 100nm to 300nm. In one embodiment, the specular reflectivity is reduced to less than 20%, and the remainder of the incident radiation can be scattered or absorbed. Only because most of the scattered radiation is absorbed elsewhere in the device and does not reach the exposed substrate, the radiation reflected by the specular surface is substantially reduced. DUV radiation only causes problems at the substrate.

[0053] In an embodiment of the present invention, the recess is elongated, e.g. Figure 8 It is shown in the form of a groove 201. Such a recess facilitates manufacturing. The orientation of the groove is not critical. The length b of the groove does not affect the function of the contaminant trap as long as the average width a of the groove is less than or equal to about 2 μm, ideally less than or equal to about 1 μm.

[0054] The surface texture of the present invention forms a contaminant trap, which can be provided on a variety of components of a lithographic apparatus. Most advantageously, the contaminant trap of the present invention is provided on a surface close to a patterning device, such as the surfaces of: a masking blade; a safety clip of a patterning device; a safety bumper of a patterning device; and a heat shield for an encoder or sensor, such as an encoder used to determine displacement of a patterning device.

[0055] The contamination trap of the present invention may also be advantageously applied in parts of a lithographic apparatus where the contamination level and / or DUV level is particularly high. An example of such a location is the interior of a source module SO. Another advantage of the present invention is that in such a location, larger molten tin drops do not adhere well to the textured surface due to the high surface tension. Therefore, tin drops that impact the surface are likely to run off or fall off, thereby maintaining the desired properties of the textured surface for a longer period of time.

[0056] Various techniques can be used to generate the desired surface texture. For example, the surface texture can be formed by interference lithography, imprint lithography, femtosecond laser texturing or selective etching. Femtosecond laser surface texturing technology is described in M ​​Faucon et al. "Surface blackening by laser texturing with high repetition rate femtosecond laser up to 1MHz" (Proc. SPIE 8972 Frontiers in Ultrafast Optics: Biomedical, Scientific and Industrial Applications XIV 89721M (March 7, 2014)), which is incorporated herein by reference. This technology can generate Figure 6 Surface texture shown.

[0057] Figure 7 A cross-sectional view of a structure obtainable by using selective etching using gold particles as an etching mask as described in "Fabrication of Ultrahigh Aspect Ratio Silicon Nanostructures using Self-Assembled Gold Metal-Assisted Chemical Etching" by J. Duran et al. (Micro / Nanolithography MEMS Journal and MOEMS 16(1): 014502 (February 2017)) (this document is incorporated herein by reference in its entirety) is shown in cross-sectional view. In an embodiment of the present invention, it is not necessary to form a structure such as Figure 7Extreme textures with aspect ratios shown. In embodiments of the invention, the aspect ratio of the valleys of the surface texture (defined as average depth c to average width a) is ideally greater than 10. Higher aspect ratios are desirable but not required.

[0058] In one embodiment of the invention, the surface texture may be formed by a process that results in significant variations in the shape and / or size of the recesses. It is not necessary for all recesses on the surface to meet the above dimensions and aspect ratios. If a higher proportion of recesses meet the specified ranges, the efficiency of the contaminant trap according to the embodiment will be improved.

[0059] In one embodiment of the invention, the surface 202 of the component is conductive, or the substrate material is conductive, or because a conductive layer is formed on the component, and the insulating layer 203 can be formed on the surface. The component or the conductive layer is grounded. This arrangement improves the capture of particles. Particles in a lithographic apparatus are often charged, for example due to EUV radiation. Charged particles will be attracted to the component by Coulomb forces. On the other hand, if the surface of the component becomes charged, the resulting electric field may have the effect of repelling positively charged particles and neutral particles. This can be prevented by grounding the surface 202 of the component.

[0060] Although embodiments of the invention may be specifically described herein in the context of a lithography apparatus, embodiments of the invention may be used in other apparatuses. Embodiments of the invention may form part of a mask inspection apparatus, a metrology apparatus, or any apparatus that measures or processes an object such as a wafer (or other substrate) or a mask (or other pattern forming apparatus). These apparatuses may generally be referred to as lithography tools. Such lithography tools may use vacuum conditions or ambient (non-vacuum) conditions.

[0061] The term "EUV radiation" may be taken to include electromagnetic radiation having a wavelength in the range 4-20 nm, for example in the range 13-14 nm. The wavelength of EUV radiation may be less than 10 nm, for example in the range 4-10 nm, such as 6.7 nm or 6.8 nm.

[0062] Although specific reference may be made herein to using a lithographic apparatus in the manufacture of ICs, it should be understood that the lithographic apparatus described herein may have other applications. Other possible applications include manufacturing integrated optical systems, guidance and detection patterns for magnetic domain memories, flat panel displays, liquid crystal displays (LCDs), thin film magnetic heads, and the like.

[0063] Although specific embodiments of the present invention have been described above, it should be understood that the present invention may be practiced in a manner other than that described. The above description is intended to be illustrative rather than restrictive. Therefore, it will be clear to those skilled in the art that modifications may be made to the described invention without departing from the scope of the claims set forth below.

Claims

1. A component of a lithographic apparatus, the component having a contaminant capture surface texture provided with recesses configured to capture contaminant particles and reduce specular reflection of DUV radiation; Wherein the texture comprises a plurality of valleys having an aspect ratio greater than or equal to about 10, the aspect ratio being defined as the ratio of an average depth of the valleys to an average width of the valleys in the plane of the surface. 2 . The component of claim 1 , wherein the width of the recess in the plane of the capture surface is less than or equal to about 2 μm.

3. A component according to claim 2, wherein the recess is elongated. 4 . The component of claim 2 , wherein the width of the recess in the plane of the capture surface is less than 1 μm.

5. The component of any one of claims 1 to 4, wherein the texture comprises a plurality of recesses having a maximum depth greater than about 1 μm. The component of claim 5 , wherein a maximum depth of the plurality of recesses is greater than about 10 μm.

7. A component according to any one of the preceding claims, wherein the contaminant capture surface has a reflectivity of less than about 20% for radiation having a wavelength in the range of 100 nm to 300 nm.

8. A component according to any one of the preceding claims, wherein the contaminant capture surface comprises an electrically conductive base layer and an insulating layer disposed on the base layer.

9. The component of claim 8, wherein the conductive base layer is connected to electrical ground.

10. A lithography apparatus comprising: A component according to any one of claims 1 to 9; an illumination system configured to illuminate the patterning device with EUV radiation; as well as A projection system is configured to project radiation patterned by the patterning device onto a substrate.

11. The lithographic apparatus according to claim 10, wherein the component is a component of the lithographic apparatus selected from the group consisting of: Label the blades, safety clips, safety bumpers and heat shields.

12. The lithographic apparatus according to claim 10 or 11, further comprising a source module for emitting EUV radiation, and wherein the component is part of a wall of the source module.

13. A method of manufacturing a contamination trap for a lithographic apparatus, the method comprising: treating a surface of a component of the lithographic apparatus to form a recess configured to capture contaminant particles and reduce specular reflection of DUV radiation; The recesses have an aspect ratio of greater than or equal to about 10, the aspect ratio being defined as the ratio of an average depth of the recesses to an average width of the recesses in the plane of the surface.

14. The method of claim 13, wherein processing the surface comprises a process selected from the group consisting of: interference lithography, imprint lithography, femtosecond laser texturing, and selective etching.

15. Use of a component according to any one of claims 1 to 9 in a lithographic apparatus for capturing contaminant particles and reducing specular reflection of DUV radiation.

16. The use according to claim 15, wherein the lithography apparatus comprises an EUV lithography apparatus.

17. Use of a surface texture in a lithography apparatus for capturing contaminant particles and reducing specular reflection of DUV radiation, the surface texture having a plurality of recesses having an aspect ratio greater than or equal to about 10, the aspect ratio being defined as the ratio of the average depth of the recesses to the average width of the recesses in the plane of the surface.

18. The use according to claim 17, wherein the lithography apparatus comprises an EUV lithography apparatus.

19. The use according to claim 17, wherein the recess has a width less than or equal to about 2 μm.

20. The use according to claim 19, wherein the recess has a width less than or equal to about 1 μm.

21. The use according to claim 17, wherein the recess has a depth greater than or equal to about 1 μm.

22. The use according to claim 17, wherein the recess has a depth greater than or equal to about 10 μm.

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