DE102021214140A1 - MOUNTING FOR A LENS, ARRANGEMENT, LITHOGRAPHY EQUIPMENT AND METHOD - Google Patents

Abstract

A mount (126) for a lens (114), comprising: a ring element (300) with holding elements (316), the holding elements (316) being integrally connected to the ring element (300), spaced apart from one another in the circumferential direction (U), and thereto are arranged to hold the lens (114); and an aperture (226) for blocking off stray light (214), the aperture (226) being formed integrally with the ring member (300).

Description

The present invention relates to a mount for a lens in a lithography system, an arrangement, a lithography system and a method for producing said mount.

Microlithography is used to produce microstructured components such as integrated circuits. The microlithography process is carried out with a lithography system which has an illumination system and a projection system (also “projection objective”). The image of a mask (reticle) illuminated by the illumination system is projected by the projection system onto a substrate coated with a light-sensitive layer (photoresist) and arranged in the image plane of the projection system, for example a silicon wafer, in order to place the mask structure on the light-sensitive coating of the substrate transferred to.

Stray light in lithography systems occurs when the working light leaves the desired beam path. This happens, for example, when the working light hits the optically effective surface of a lens and is reflected there in undesirable directions. The case also arises that the working light strikes plane surfaces or plane bevels, for example of lenses, and is directed there in undesirable directions. As a rule, efforts will be made not to allow the working light to impinge on such flat surfaces or flat bevels. In principle, this can be controlled in lithography systems with the aid of the lighting settings. However, experience has shown that lighting settings are changed by the end customer, i.e. by the chip manufacturer. This, for example, to improve structures on chips produced with the help of the lithography system. Such lighting settings are not always foreseeable for the manufacturer of the lithography system or the projection lens.

The occurrence of scattered light is problematic in several respects. Sometime this can directly affect the picture negatively. This happens when the scattered light itself is thrown back into the beam path and reaches the substrate to be exposed. Furthermore, the scattered light can lead to undesired, in particular local, heating of optical elements in the lithography system. The corresponding thermal distortion can in turn degrade the image. Furthermore, the scattered light can have a damaging effect on optical elements or other parts in the housing of the lithography system. In particular, it can lead to the decomposition of adhesive.

It has therefore long been known to use lens hoods in lithography systems. This is for example in the publication DE 2015 207 159 A1 described. This is what this publication calls microstructures in the form of diffraction gratings that are introduced into the lens material. Furthermore, a defined surface roughness is used to avoid reflections on flank surfaces. The publication also mentions the possibility of providing a reflective coating. This directs the light it reflects into a non-critical area in which it can be absorbed.

Against this background, it is an object of the present invention to provide an improved mount for a lens.

• ein Ringelement mit Halteelementen, wobei die Halteelemente
  • einstückig mit dem Ringelement verbunden,
  • in Umfangsrichtung voneinander beabstandet sind, und dazu eingerichtet sind, die Linse zu halten; und
• eine Blende zum Abblenden von Streulicht, wobei die Blende einstückig mit dem Ringelement gebildet ist.

Accordingly, according to a first aspect, a mount for a lens in a lithography system is provided. The version shows:

• a ring element with holding elements, wherein the holding elements
  • integrally connected to the ring element,
  • circumferentially spaced from each other and adapted to hold the lens; and
• a shade for cutting off stray light, the shade being formed integrally with the ring member.

A diaphragm or lens hood formed in one piece with the ring element advantageously leads to a compact design. In addition, such a screen can be easily manufactured. Furthermore, there are thermal advantages. This is because heat can be conducted favorably from the panel via the one-piece connection into the ring element.

The ring element is in particular in the form of a circular ring or an oval ring. The ring element is preferably closed and includes an opening. Preferably, the ring member includes an inner perimeter and an outer perimeter. The inner perimeter faces the opening. On the outer circumference, the ring element can have connection means, such as screw holes. The mount can be fastened in a lithography system, in particular in a projection lens of the same, with the aid of the connecting means. The retaining members may protrude inward from the inner periphery of the ring member. Preferably, the holding elements each have an end that faces the ring element and an end that faces away from it. The end of a respective holding element which faces the ring element is preferably formed in one piece with the ring element. The holding elements are preferably arranged at a uniform distance from one another in the circumferential direction. In embodiments, the holding elements each have at least one edge (also referred to as “roof edge”) on which the lens rests. The lens is preferably glued to a respective holding element in areas on both sides of and adjacent to the roof edge.

In the present case, “in one piece” is to be understood as meaning that the ring element together with its holding elements and the screen are made of one piece and of one and the same material. It is manufactured in a primary shaping step, for example by casting, extruding, etc. The ring element, including its retaining elements, and the panel are preferably made of metal, in particular steel or another alloy. In particular, a nickel-iron alloy such as Invar comes into consideration as the material.

The screen or its screen elements, which will be explained in more detail later, preferably extend in one plane. This plane preferably lies in the plane of the opening enclosed by the ring element or parallel thereto. The screen or screen elements preferably cover at least 3%, preferably at least 5% and even more preferably at least 10% of the opening defined by the ring element.

“Stray light” is to be understood as meaning that light which moves outside the desired beam path in the optical system (e.g. the arrangement or the lithography system in which the lens is installed). The light that moves in the desired beam path is referred to as useful or working light.

The panel can include multiple panel elements. The screen or its screen elements preferably extend—at least in total—more than 30%, preferably more than 50%, even more preferably more than 70% or completely along the inner circumference of the ring element.

In the present case, a “lens” is understood to mean a transparent, in particular disc-shaped element, of which at least one of the two surfaces is curved. Transmitted light is deflected towards the center of the light beam (in the case of a converging lens) or scattered outwards (in the case of a diverging lens).

The ring element with its holding elements and the screen are preferably milled from a material blank and, if appropriate, also produced by bending one or more of these parts.

The mount is designed to be suitable, in particular, for installation in an optical system, in particular in the field of lithography. The diaphragm masks out stray light in the optical system accordingly. Examples of an optical system are a projection objective or some other arrangement comprising a lens or in a lithography system.

According to one embodiment, the screen or screen elements thereof are mechanically decoupled from the holding elements.

The mechanical decoupling is brought about by the fact that there is no direct mechanical connection between the screen or its screen elements and the holding elements. The screen or its screen elements and the holding elements are only connected to one another by the ring element.

According to a further embodiment, the screen or screen elements thereof are spaced apart from a respective holding element with the aid of a gap.

A corresponding gap can also be provided between adjacent screen elements and/or between one, several or all pairs, each comprising a screen element and a holding element. With the help of the gap, a mechanical decoupling of the screen or the screen elements from the holding elements is achieved in a simple manner. The gap or the several gaps can be produced simply by eroding, for example. The mechanical decoupling is particularly advantageous with regard to the transfer of thermal stresses and/or vibrations between the holding elements and the panel or its panel elements.

According to a further embodiment, the screen or screen elements thereof are arranged at least in sections in the circumferential direction between the holding elements.

Correspondingly, the screen or the screen elements screen off stray light in the intermediate space between the holding elements.

According to a further embodiment, the screen or screen elements thereof are arranged at least in sections radially further inwards than the holding elements.

As a result, the anti-glare effect of the screen or screen elements can be further improved. “Radial” here refers to the imaginary center point of the opening enclosed by the ring element.

According to a further embodiment, the panel is composed of a plurality of panel elements, with each panel element having at least a first and a second section, the first section being attached in one piece to the ring element and the second section being arranged in the circumferential direction adjacent to one of the holding elements.

According to a further embodiment, the respective screen element has a third section which is arranged radially adjacent to the holding element.

A respective screen element preferably protrudes beyond a respective holding element and shields scattered light in an area directly in front of the free end of a respective holding element.

According to a further embodiment, a respective holding element is arranged between two screen elements, with the two screen elements encompassing the respective holding element at its radially inner end.

A corresponding arrangement is easy to manufacture. In addition, the two panel elements surrounding the respective holding element can be embodied symmetrically. The axis of symmetry is a radial line here. Such symmetry is advantageous with respect to thermal deformations.

According to a further embodiment, the screen or the respective screen element has an effective surface, the effective surface forming a starting point for a bending tool in order to bend the screen or the respective screen element away from the holding element in the axial direction.

The mount can be produced particularly easily by bending the screen or the respective screen element and/or the holding elements. In embodiments, this is also possible without a dedicated effective area. In particular, the bending can create an axial gap between the diaphragm or a respective diaphragm element and the respective opposite lens surface. In the present case, “axial” means a direction perpendicular to a plane which encompasses the opening enclosed by the ring element.

According to a further embodiment, the respective holding element has a roof edge for the lens to rest against, the axial distance between the roof edge and a roof-edge-side surface of the diaphragm or a respective adjacent diaphragm element being less than 1 mm, preferably less than 0.6 mm and/or or more than 0.1 mm.

As a result, the area in which scattered light can emerge from the beam path is advantageously limited. At the same time, the distance ensures a particularly thermal and other mechanical decoupling of the lens from the diaphragm or the diaphragm elements and improves the flow of flushing gas, as will be explained in more detail later.

According to a further embodiment, the gap between a respective holding element and the screen or a respective screen element has a width of less than 1.5 mm, preferably less than 0.9 mm and/or more than 0.5 mm.

This measure also reduces the amount of scattered light that can escape from the beam path and improves mechanical decoupling and flushing with flushing gas.

According to a further embodiment, the screen or the screen elements have one or more through-openings, which are arranged in one or respective bending areas of the screen or the screen elements and/or in the ring element.

The material is locally weakened with the aid of the through openings, so that a defined bending is possible in these areas. In addition, such through openings can define the flow of heat into the ring element, in particular in that the flow of heat is guided into the ring element and away from the holding elements. Such through openings can also improve a gas flow. In particular, a flushing gas, in particular nitrogen, which is located inside the lithography system or the projection lens, can flow off better as a result. The passage openings can in particular be incisions, ie elongated recesses. The one or more through-openings in the ring element can be provided in addition to or as an alternative to the through-openings in the bending areas. The through openings in the ring element can also improve the flow of purge gas. The through-openings in the ring element can have a diameter greater than 3 mm, preferably greater than 6 mm, for example. For example, two, four, eight, twelve or more such through openings, in particular bores, can be provided.

According to a second aspect, an arrangement, in particular a projection lens, with a lens and a mount, as described above, is provided. The holding elements hold the lens.

In particular, the screen or the screen elements can be arranged in such a way that they cover one or more plane surfaces and/or plane bevels of the lens or another lens (which is also part of the arrangement). As a result, no scattered light reaches these plane surfaces or plane bevels or cannot be reflected on them, so that further propagation of the scattered light in the lithography system or in the housing of the projection objective is avoided.

According to a third aspect, a lithography system, in particular a DUV lithography system, is provided with an arrangement as described above.

DUV stands for "Deep Ultraviolet" and describes a working light wavelength between 30 nm and 250 nm.

In particular, the lithography system has a further lens, with the diaphragm of the mount being arranged between the lenses and a minimum distance between the lenses in the axial direction being less than 1% of the diameter of the smaller of the two lenses.

The axial direction here refers to the central axis of the socket or its passage opening.

• subtraktives maschinelles Bearbeiten eines einstückigen Materialblocks zum Erhalt der Fassung.

According to a fourth aspect, there is provided a method of manufacturing a socket as described above. The method includes in particular the step:

• subtractively machining a one-piece block of material to obtain the socket.

The subtractive machining includes, in particular, milling and/or eroding.

According to one embodiment of the method, the screen or the screen elements is or are bent away from the holding elements in the axial direction.

As a result, the screen or the screen elements can be produced easily.

The embodiments and features described for the first aspect apply correspondingly to the other aspects described here, and vice versa.

Further possible implementations of the invention also include combinations of features or embodiments described above or below with regard to the exemplary embodiments that are not explicitly mentioned. The person skilled in the art will also add individual aspects as improvements or additions to the respective basic form of the invention.

• 1 zeigt eine schematische Ansicht einer Ausführungsform einer DUV-Lithographieanlage;
• 2 zeigt einen Teilschnitt II aus 1;
• 3 zeigt in perspektivischer Ansicht eine Fassung aus 2;
• 4 zeigt perspektivisch einen Schnitt IV-IV aus 3;
• 5 zeigt eine Ansicht V aus 4;
• 6 zeigt eine Ansicht VI aus 4; und
• 7 zeigt die Ansicht aus 4, jedoch gemäß einem weiteren Ausführungsbeispiel.

Further advantageous refinements and aspects of the invention are the subject matter of the dependent claims and of the exemplary embodiments of the invention described below. The invention is explained in more detail below on the basis of preferred embodiments with reference to the enclosed figures.

• 1 shows a schematic view of an embodiment of a DUV lithography system;
• 2 shows a partial section II 1 ;
• 3 shows a perspective view of a socket 2 ;
• 4 shows a section IV-IV in perspective 3 ;
• 5 shows a view V from 4 ;
• 6 shows a view VI 4 ; and
• 7 shows the view 4 , but according to a further embodiment.

Elements that are the same or have the same function have been provided with the same reference symbols in the figures, unless otherwise stated. Furthermore, it should be noted that the representations in the figures are not necessarily to scale.

1 FIG. 1 schematically shows a DUV lithography system 100, which includes a beam shaping and illumination system 102 and a projection system 104 (here also referred to as “projection objective”). The beam shaping and illumination system 102 and the projection system 104 are preferably each arranged in a vacuum housing, not shown. Each vacuum housing is evacuated using an evacuation device, not shown. The vacuum housings are surrounded by a machine room, not shown, in which drive devices can be provided for mechanically moving or adjusting optical elements. Furthermore, you can also electrical controls and the like can be arranged in the machine room.

The DUV lithography system 100 includes a light source 106. An ArF excimer laser, for example, can be provided as the light source 106, which emits radiation 108 at, for example, 193 nm. The radiation 108 is bundled in the beam shaping and illumination system 102 and the desired operating wavelength (work light) is filtered out of the radiation 108 . The beam shaping and illumination system 102 may include optical elements, such as mirrors or lenses, not shown. After passing through the beam shaping and illumination system 102 , the radiation 108 is directed onto a photomask (reticle) 110 . The photomask 110 is designed as a transmissive optical element and can be arranged outside of the systems 102, 104. The photomask 110 has a structure which is imaged on a wafer 112 in reduced form by means of the projection system 104 .

The projection system 104 has a plurality of lenses 114, 116, 118 and/or mirrors 120, 122. It should be noted that the number of lenses and mirrors shown herein is purely exemplary and not limited to the number shown.

An air gap between the last lens (not shown) and the wafer 112 can be replaced by a liquid medium 124 which has a refractive index greater than 1. The liquid medium 124 can be, for example, ultrapure water. Such a structure is also referred to as immersion lithography and has an increased photolithographic resolution. The medium 124 can also be referred to as an immersion liquid.

The systems 102, 104 are preferably traversed by a flushing gas, in particular nitrogen (in 1 Not shown). The task of the flushing gas is in particular to keep the finest particles, in particular abraded material, away from the optical elements, ie in particular the lenses and mirrors. In other embodiments, however, such a flushing gas can be dispensed with.

Furthermore shows 1 that the lenses 114, 116 arranged directly one behind the other are each held by a mount 126, 128 in the projection system 104. The projection system 104 or parts thereof are also referred to as an “arrangement” in the present case.

2 illustrates a detail of a longitudinal section II 1 , in which the lenses 114, 116 together with associated mounts 126, 128 are shown. 2 also shows a central axis 200 of the socket 126 or of its opening 302 (see 3 ). This can coincide with the longitudinal center axis of the projection system or projection objective 104 . The sockets 126, 128 can be flanged together in the axial direction A (along the central axis 200) and in the circumferential direction U (see 3 ) based on the central axis 200 form a closed housing 206 or parts thereof. Other housing parts - for example in 2 designated by the reference numeral 202 - may be connected to sockets 126,128.

Furthermore shows 2 a lens hood 204 shown purely by way of example, which is arranged within a volume 208 of the housing 206 . The stray light shield 204 has the task of preventing stray light 210 from propagating in the volume 208 . The scattered light 210 is a portion of light in the radiation 108 which does not move in the desired beam path 212 . The reason for this can be, for example, inaccuracies in the manufacture of a lens (not shown) connected upstream of the lens 114, which lead to unforeseen refractions of light. The stray light 210 is largely absorbed by the stray light screen 204 .

Likewise, stray light 214 occurs in a gap 216 between the lenses 114,116. The gap 216 is made comparatively narrow. This is because a minimum distance d between the lenses 114, 116 in the axial direction A is comparatively small. In particular, the distance d is less than 1% of the diameter D ₁₁₄ of the lens 114, which can correspond to a value of less than 1 cm, for example. In particular, the diameter D ₁₁₄ (maximum diameter of the same) is smaller than a maximum diameter D ₁₁₆ of the lens 116. The lenses 114, 116 can each have a concave section 218, 220 opposite one another. The concave sections 218, 220 have the respective optically active areas of the lenses 114, 116.

The concave sections 218 , 220 are each peripherally delimited by edge regions 222 , 224 - in relation to the central axis 200 . The lens 114 rests on the mount 126 in the edge region 222, as will be described in more detail later. The edge area 224 of the lens 116 forms a plane surface. The socket 126 includes a screen 226 (also "stray light screen"), which prevents the scattered light 214 from the beam path 212 from falling onto the planar surface 224, from where it would be reflected further into the volume 208 and could cause adverse effects there. The adverse effects include, for example, thermal expansion, degradation of adhesive due to exposure to light, etc.

Based on 3 until 6 a first exemplary embodiment with respect to the socket 126 including the aperture 226 is explained in more detail below. 3 shows a perspective view of the socket 126, 4 make a section IV-IV 3 , 5 a top view V from 4 and 6 a view VI out 4 .

The socket 126 includes a ring element 300. The ring element 300 encloses an opening 302. Through the opening 302, the in 2 shown beam path 212 of the radiation 108. The ring element 300 is circumferentially closed with respect to the central axis 200. The circumferential direction is in 3 marked with U.

The ring element 300 can be composed of a first section 304 and a second section 306, for example. The first section 304 can also be referred to as the outer section in relation to the radial direction R (in relation to the central axis 200), and the second section 306 as the inner section. For example, the outer portion 304 may have a plurality of bores 308 in a flange 310 thereof. With the help of the bores 308, the sockets 126, 128 and the other housing parts 202 are fastened to one another or flanged to one another to form the housing 206.

The inner portion 306 is attached to the outer portion 304 via mechanical decoupling elements 312, such as flexure hinges. Otherwise, the inner and outer sections 304, 306 are separated from one another by a gap 314. The configuration of the ring element 300 described above is purely exemplary and can vary depending on the projection objective 104 and the lithography system 100 .

Retaining elements 316 are provided on the inside of ring element 300 (relative to longitudinal center axis 300). The holding elements 316 are formed in one piece with the ring element 300, in particular with its inner section 306. The holding elements 316 are also provided spaced apart from one another in the circumferential direction U, in particular spaced evenly apart from one another. The holding elements 316 hold the lens 114, whereby this with its edge region 222 (see 2 ) on a so-called roof edge 318 (see 2 ) of a respective holding element 316 rest. In areas 400 (see 2 and 4 ) On both sides of the roof edge 318, the holding elements 318 are glued to the edge area 222 of the lens 114.

The aperture 226 is in the embodiment 3 until 6 designed as a one-piece panel. This means that it extends in one piece and closed in the circumferential direction U around the center axis 200 . A second embodiment will be discussed later in connection with 7 explained, in which the panel 126 is composed of several panel elements 700, 702, 704.

returning to 4 it is shown there that the screen 226 is formed in one piece with the ring element 300 or the inner section 306 of the same. The ring element 300 or its inner section 306 is preferably produced in one piece with the holding elements 316 and the screen 226 in that these are produced from a blank made of the same material. The blank is produced in a primary forming process such as casting. A metal is particularly suitable as the material for the blank and correspondingly for the ring element 300 , the holding elements 316 and the screen 226 . Preferably, the manufacturing process or machining process of the blank includes subtractive machining processes, such as milling and eroding, and a forming process, in particular bending, to the 3 until 6 produce socket 126 shown.

According to the exemplary embodiment, the aperture 226 comprises an in 4 visible axial portion 402 and a radial portion 404, where "axial" and "radial" refer to the central axis 200. At the same time, the holding element 316 comprises a 2 and 4 to be seen axial portion 406 and a radial portion 408. The radial portion 408 carries at its - in 4 to be seen - upper side the roof edge 318. The axial sections 402, 406 each include one end 416, 418 of the ring element 300 or its inner section 306 in one piece. The radial sections 404, 408 can be at an angle α (see 4 ) and β (see 2 ) connect to the respective axial sections 402 and 406, respectively. The angles α and β can, for example, each be 90° or deviate slightly from one another, as explained in more detail below. The axial section 402 and the radial section 404 (the latter only partially) are each arranged between the holding elements 316 in the circumferential direction U.

A respective holding element 316 can be inserted through a gap 410 (see 5 ) be separated from the aperture 226. The gap 410 extends from the ring element 300 or its inner section 306 in the plan view 5 U-shaped around the support member 316 such that the support member 316 is entirely spaced from the bezel 226. As a result, the holding elements 316 and the panel 226 are mechanically decoupled from one another. This is in both mechanical and thermal terms. In particular, a so-called so-called cross-talk between these parts is prevented.

In particular, the gap 410 spaces the axial sections 402, 406 and the radial sections 404, 408 from one another. The width B ₄₁₀ of the gap 410 is both in the circumferential direction U and in the radial direction R (see FIG 5 ) preferably less than 1.5 mm, preferably less than 0.9 mm and even more preferably less than 0.5 mm. In particular, the radial section 404 includes a partial section 412 (also referred to as “third section”), which extends radially in front of the holding element 316 or in front of its radial section 408 . In other words, the partial section 412 is located directly opposite the free end 414 of the radial section 408, namely viewed radially inward in relation to the central axis 200.

In relation to 6 it should be noted that there the lens 114 - deviating from 4 - is shown. The view of 6 corresponds to the viewing direction as seen in the radial direction R (view in the direction of arrow VI in 4 ). It can be seen here that between the edge area 222 (underside of the lens 114) and an upper side 420 (see 4 and 6 ) of the radial section 404 of the diaphragm 226 there is an axial gap 422. The width B ₄₂₂ of the gap 422 is preferably less than 1 mm, preferably less than 0.6 mm and more than 0.1 mm. The width B ₄₂₂ (the same applies to the width B ₄₁₀ of the gap 410) preferably designates a minimum gap dimension. This means, for example with regard to the gap 422, that this, depending on where along the surface 420 (see 4 ) the gap 422 (see 6 ) is measured, a different gap size B ₄₂₂ results. However, the value ranges described above relate to the smallest detectable gap dimension B ₄₂₂ along the surface 420.

The gap size B ₄₂₂ can be controlled in particular by bending the holding element 316 or the screen 226 or the respective radial section 408 or 404 upwards or downwards (ie in opposite directions along the axial direction A). The radial section 404 is preferably bent during the manufacture of the socket 126 with the aid of a bending tool - in 4 - pressed axially downwards (ie, away from the lens 114) so that the angle α is less than 90°. For example, the angle α has a value between 80 and 90°, in particular between 80 and 88°. The angle β (see 2 ) is 90°, for example.

Based on 7 a second exemplary embodiment will now be explained in which, as already mentioned, the screen 226 has a plurality of screen elements 700, 702, 704. In particular, the two diaphragm elements 700, 702 with a respective partial section 412 encompass the free end 414 of the radial section 408 of the holding element 316. The partial sections 412 have a gap 706 with respect to one another. For the width B ₇₀₆ of the gap 706, what has already been said about the gap 410 with the width B ₄₁₀ applies. In particular, the gap 706 is preferably also produced by eroding. The diaphragm elements 700, 702 can be designed symmetrically with respect to a radial axis of symmetry 707, which leads through the gap 706.

Furthermore, in 7 to recognize that the screen element 704 is arranged in the circumferential direction U between two screen elements 700, 702 and itself is not directly adjacent to one of the holding elements 316. In this exemplary embodiment, there are at least three screen elements 700, 702, 704 between two holding elements 316 in each case. A gap 708 or 710 is provided between the screen elements 704 and 700 or 702, respectively, with a width B ₇₀₈ or B ₇₁₀ . With regard to widths B ₇₀₈ and B _710, the same applies as for width B ₄₁₀ . The screen element 704 includes an axial section 712 and a radial section 714 which extend parallel to the sections 402 and 404 of the adjacent screen elements 700 and 702, respectively. The screen elements 700, 702, 704 define a substantially continuous edge 716 which defines the opening 302 (see FIG 3 ) limited.

Furthermore, the screen elements 700, 702, 704 each have an axial step 718. The step 718 forms a starting point for a bending tool (not shown) to bend the screen elements 700, 702, 704 in the axial direction A in 7 to bend down.

In order to facilitate bending, cuts 720, 722 extending in the circumferential direction U are preferably provided in the screen elements 700, 702, 704 on both sides. Instead of the incisions 720, 722, other forms of weakening of the material could also be provided, or other openings, passages or recesses could be provided in a respective screen element 700, 702, 704. Starting from the gap 708, 410 or 708, 710, the incisions 720, 722 extend in the circumferential direction into a respective screen element 700, 702, 704. The cuts 720, 722 are preferably provided in a respective corner region 724. In the corner region 724, a respective radial section 404, 714 adjoins a respective axial section 402, 712 of a respective screen element 700, 702, 704. With help The incisions 720, 722 can also be used to control a flow of a purge gas through the projection system 104. A corresponding purge gas flow is in 2 labeled 228. The flushing gas, in particular nitrogen, is used to remove particles, in particular abraded particles, from the area of the optically effective lens areas (cf. reference numerals 218, 220).

In addition or as an alternative to the incisions 720, 722, the ring element 300 or its inner section 306 can have passages, in particular bores 726, for leading out the flushing gas (cf. reference number 228). These can preferably have a diameter D ₇₂₆ of between 4 and 8 mm, for example. Furthermore, the flushing gas 228 is passed through the gaps 410, 706, 708, 710 (see 7 ) and gap 422 (see 6 ) between the lenses 114, 116.

The above aspects cannot only be applied to a socket 126 for a DUV lithography system 100. Rather, an application in the entire field of optics, in particular in the field of lithography, is conceivable. For example, such a socket 126 can also be used in measuring devices or production devices in the field of lithography.

Although the invention has been described here on the basis of preferred exemplary embodiments, it is not limited thereto but can be modified in many ways.

Reference List

100

DUV lithography system

102

Beam shaping and lighting system

104

projection system

106

light source

108

radiation

110

photomask

112

wafers

114

lens

116

lens

118

lens

120

Mirror

122

Mirror

124

medium

126

version

128

version

200

central axis

202

housing part

204

lens hood

206

Housing

208

volume

210

scattered light

212

beam path

214

scattered light

216

space

218

concave section

220

concave section

222

edge area

224

edge area

226

cover

228

purge gas flow

300

ring element

302

opening

304

outer section

306

inner section

308

drilling

310

flange

312

flexure joint

314

gap

316

holding element

318

roof edge

400

Area

402

axial section

404

radial section

406

axial section

408

radial section

410

gap

412

section

414

End

416

End

418

End

420

surface

422

gap

700

aperture element

702

aperture element

704

aperture element

706

gap

707

axis of symmetry

708

gap

710

gap

712

axial section

714

radial section

716

edge

718

Step

720

incision

722

incision

724

corner area

726

drilling

A

axial direction

B410

gap width

B422

gap width

B706

gap width

B708

gap width

B710

gap width

i.e

axial distance

D114

diameter

D116

diameter

D726

diameter

R

radial direction

u

circumferential direction

a

angle

β

angle

QUOTES INCLUDED IN DESCRIPTION

This list of documents cited by the applicant was generated automatically and is included solely for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.

Patent Literature Cited

• DE 2015207159 A1 [0005]

Claims (15)

Mount (126) for a lens (114), comprising: a ring element (300) with holding elements (316), wherein the holding elements (316) integrally connected to the ring element (300), spaced from each other in the circumferential direction (U), and arranged to hold the lens (114); and a screen (226) for screening off stray light (214), the screen (226) being formed integrally with the ring member (300). version after claim 1 , wherein the diaphragm (226) or diaphragm elements (700, 702, 704) thereof is mechanically decoupled from the holding elements (316). version after claim 1 or 2 wherein the screen (226) or screen elements (700, 702, 704) thereof is spaced from a respective support element (316) by means of a gap (410). Version after one of Claims 1 - 3 , wherein the screen (226) or screen elements (700, 702, 704) thereof is arranged at least in sections in the circumferential direction (U) between the holding elements (316). Version after one of Claims 1 - 4 , wherein the screen (226) or screen elements (700, 702, 704) thereof is arranged at least in sections (412) radially further inwards than the holding elements (316). Version after one of Claims 1 - 5 , wherein the screen (226) is composed of a plurality of screen elements (700, 702), each screen element (700, 702) having at least a first and a second section (402, 404), the first section (402) being integrally attached attached to the ring element (300) and the second section (404) is arranged in the circumferential direction (U) adjacent to one of the holding elements (316). version after claim 6 , wherein the respective diaphragm element (700, 702) has a third section (412) which is arranged radially inwardly adjacent to the holding element (316). version after claim 7 wherein a respective holding element (316) is arranged between two screen elements (700, 702), the two screen elements (700, 702) encompassing the respective holding element (316) at its radially inner end (414). Version after one of Claims 1 - 8th , wherein the screen (226) or the respective screen element (700, 702, 704) has an active surface (718), the active surface (718) forming a starting point for a bending tool in order to bend the screen (226) or the respective screen element (700 , 702, 704) in the axial direction (A) away from the holding elements (316). Version after one of Claims 1 - 9 , wherein the respective holding element (316) has a roof edge (318) for abutment of the lens (114) against this, with an axial distance (B ₄₂₂ ) of the roof edge (318) to a roof-edge-side surface (420) of the screen (226) or of a respective adjacent screen element (700, 702, 704) is less than 1 mm, preferably less than 0.6 mm and/or more than 0.1 mm and/or the gap (410) between a respective holding element (316) and the screen (226) or a respective screen element (700, 702) has a width (B ₄₁₀ ) of less than 1.5 mm, preferably less than 0.9 mm and/or more than 0.5 mm. Version after one of Claims 1 - 10 , wherein the panel (226) or the panel elements (700, 702, 704) have one or more through openings (720, 722, 726) which are in one or respective bending areas (724) of the panel (226) or the panel elements (700, 702, 704) and/or in the ring element (300). Arrangement (104), in particular projection lens, with a lens (114) and a mount (126) according to one of Claims 1 - 11 , wherein the holding elements (316) hold the lens (114). Lithography system (100), in particular DUV lithography system, with an arrangement (104). claim 12 , wherein in particular a further lens (116) is provided, wherein the diaphragm (226) is arranged between the lenses (114, 116) and a minimum distance (d) between the lenses (114, 116) in the axial direction (A) is less than 1% of the diameter (D ₁₁₄ ) of the smaller of the two lenses (114, 116). A method of making a socket (126) according to any one of Claims 1 - 11 comprising the step of: subtractively machining a one-piece block of raw material to obtain the socket (126). procedure after Claim 14 , wherein the aperture (226) or the aperture elements (700, 702, 704) is/are bent away from the holding elements (316) in the axial direction (A).

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