DE102021203723A1 - CONNECTION ARRANGEMENT, PROJECTION EXPOSURE EQUIPMENT AND METHOD - Google Patents

Abstract

A connection arrangement (100) for the solderless and electrically conductive connection of a press-in element (114A, 114B) to a circuit board (104), having a metal sleeve (112) provided at an opening (110) in the circuit board (104), and the press-in element (114A, 114B) which has a press-in section (134) which is pressed into the metal shell (112) in such a way that the press-in section (134) is cold-welded to the metal shell (112), and an aperture (146) for establishing an electrical connection with the press-in element (114A, 114B), wherein the opening (146) viewed along an axis of symmetry (132) of the press-in element (114A, 114B) is guided at least into the metal sleeve (112), so that the electrical connection is viewed along the axis of symmetry (132). can be produced at the height of the metal sleeve (112).

Description

The present invention relates to a connection arrangement for the solderless and electrically conductive connection of a press-in element to a printed circuit board, a projection exposure system with at least one such connection arrangement, and a method for producing such a connection arrangement.

Microlithography is used to produce microstructured components such as integrated circuits. The microlithography process is carried out using a lithography system which has an illumination system and a projection system. 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.

Driven by the striving for ever smaller structures in the manufacture of integrated circuits, EUV lithography systems are currently being developed which use light with a wavelength in the range from 0.1 nm to 30 nm, in particular 13.5 nm. In such EUV lithography systems, because of the high absorption of light of this wavelength by most materials, reflective optics, ie mirrors, must be used instead of—as hitherto—refractive optics, ie lenses.

In such EUV lithography systems it is necessary to wire a wide variety of actuators, sensors, cables and printed circuit boards under EUV conditions. In this case, for example, in the case of an electrical connection between a cable and a printed circuit board, attention must be paid to a small installation space requirement. Due to the EUV conditions, in particular the vacuum environment and the atmosphere containing hydrogen, only a limited selection of materials is possible. For example, soldered connections are unsuitable.

Against this background, it is an object of the present invention to provide an improved connection arrangement.

Accordingly, a connection arrangement for the solderless and electrically conductive connection of a press-in element to a printed circuit board is proposed. The connection arrangement comprises a metal sleeve provided at an opening of the circuit board and the press-in element, which comprises a press-in section, which is pressed into the metal sleeve in such a way that the press-in element is cold-welded to the metal sleeve, and a breakthrough for establishing an electrical connection with the press-in element, wherein viewed along an axis of symmetry of the press-in element, the opening is made at least as far as the metal sleeve, so that the electrical connection can be made at the height of the metal sleeve when viewed along the axis of symmetry.

Due to the fact that the press-in element is cold-welded to the metal sleeve, a soldered connection can advantageously be dispensed with. This makes it possible to use the connection arrangement under EUV conditions. The cold weld thus ensures both a mechanical and an electrically conductive connection between the press-in element and the metal sleeve. Furthermore, plug connectors can also be dispensed with. These are usually made of plastics, which can only be used to a very limited extent under EUV conditions. Due to the fact that the electrical connection can be made at the level of the metal sleeve, the smallest possible installation space can be achieved when viewed along the axis of symmetry.

In particular, the printed circuit board can be any type of non-flexible printed circuit board. For example, ceramic, glass or FR4 can be used for the printed circuit board. Conductor tracks can be provided on or on the printed circuit board, which can be electrically conductively connected to the metal sleeve. The conductor tracks can also be embedded in the printed circuit board. The printed circuit board can also be referred to as a circuit board. The opening can also be referred to as a bore or breakthrough. The printed circuit board can have a large number of openings, bores or breakthroughs. Each opening can have such a metal sleeve. The metal sleeve can, for example, be attached to the opening during the manufacture of the printed circuit board. For example, this can be done by galvanic deposition of the metal sleeve. The metal sleeve preferably has a circular-cylindrical inner surface.

A cold welded connection or cold pressure welded connection is made under high pressure and, in contrast to other welding methods, below the recrystallization temperature of the individual parts. The two parts, in this case the press-in element and the metal sleeve, remain in a solid state, but plastic deformation occurs with the contact surfaces of the metal sleeve and the press-in element coming very close together. In particular, the metal sleeve is plastically deformed. The press-in element can also be plastically deformed. The intensive contact between the two contact surfaces results in a stable connection between the press-in element and the metal sleeve. This cold The welded connection is electrically conductive and mechanically connects the press-in element to the metal sleeve.

The press-in element is preferably constructed rotationally symmetrically to the axis of symmetry. The press-in section itself, on the other hand, does not have to be rotationally symmetrical to the axis of symmetry. The breakthrough is preferably constructed rotationally symmetrically to the axis of symmetry. The breakthrough can completely break through the press-in element viewed along the axis of symmetry. In this case, the breakthrough can be a through hole. The breakthrough can also only partially break through the press-in element. In this case, the breakthrough can be a blind hole. However, the breakthrough runs at least as far as the metal sleeve. That is to say that the opening, viewed along the axis of symmetry, is placed at least in sections within the metal sleeve.

The opening can have a thread, in particular an internal thread. The electrical connection to the press-in element can be established with the help of the opening, for example by screwing a screw or a bolt into the opening. The electrical connection is implemented in particular where a force, for example a force applied by a screw to the press-in element, acts on or in the opening. A screw-through connection can also be used to produce the electrical connection. The electrical connection can include a cable that is connected to the press-in element, in particular to the opening. The fact that the electrical connection can be established “at the level” of the metal sleeve viewed along the axis of symmetry means here that the electrical connection is located within the metal sleeve when viewed along the axis of symmetry.

According to one embodiment, the press-in portion is polygonal and comprises edges running along the axis of symmetry of the press-in element, only the edges being cold-welded to the metal sleeve.

The press-in element is preferably constructed essentially rotationally symmetrically with respect to the axis of symmetry. The press-in element has a disc-shaped base section which can bear against the printed circuit board. The base portion has an outside diameter that is larger than an inside diameter of the metal shell. The press-in section extends out of the base section. The press-in section can be, for example, in the form of a cube or cuboid. In the present case, “polygonal” means, for example, triangular, square, pentagonal or with any number of corners. In particular, the press-in section is polygonal when viewed along the axis of symmetry. That is, the press-fit portion is polygonal in a plan view or in a cross section perpendicular to the axis of symmetry. Only the edges of the press-fit portion come into contact with the metal shell. As a result, the surface pressure at the edges can be increased, so that cold welding of the edges of the press-in section to the metal sleeve occurs. On the other hand, full-area contact of the press-in section with the metal sleeve could result in the metal sleeve being pressed out of the opening in the printed circuit board. This is undesirable.

According to a further embodiment, the edges lie on a common auxiliary circle, with a diameter of the auxiliary circle being larger than an inner diameter of the metal sleeve.

As previously mentioned, the metal shell includes a circular cylindrical inner surface having the aforementioned inner diameter. Because the diameter of the auxiliary circle is at least slightly larger than the inner diameter of the metal sleeve, the metal sleeve is plastically deformed in the area of the edges when the press-fit section is pressed into the metal sleeve, which leads to cold welding. The edges can also be plastically deformed. For example, the auxiliary circle is a few tenths of a millimeter larger than the inner diameter of the metal sleeve. However, the diameter of the auxiliary circle is selected in such a way that the metal sleeve is not penetrated radially by the edges. Minor deformations of the printed circuit board, however, are permissible.

According to a further embodiment, the press-in section is square or star-shaped when viewed along the axis of symmetry.

In the case of the square geometry, the press-in portion has four edges that are in contact with the metal shell. This means, in particular, that the press-in section is square in cross section, viewed perpendicularly to the axis of symmetry. Viewed along the axis of symmetry, the press-in section can, however, also be triangular or any polygonal. In the case of the star-shaped geometry, the press-fit section has any number of edges. For example, about twenty edges can be provided. Because a large number of edges are provided, a smaller inner diameter of the metal sleeve can be selected for the star-shaped press-in section in comparison to the square press-in section. As the number of edges increases, so does the current-carrying capacity of the connection.

According to a further embodiment, the connection arrangement has the smallest possible installation space as viewed along the axis of symmetry due to the pressing of the press-in section into the metal sleeve.

The combination of the press-in element with the metal sleeve provided on the printed circuit board makes it possible to achieve the lowest possible overall height of the connection in comparison to arrangements known in-house.

According to a further embodiment, the connection arrangement also includes a cable lug for receiving a cable, the cable lug being electrically conductively connected to the opening in the press-in element.

The cable lug preferably includes a sleeve section in which the cable can be accommodated. The barrel portion may be crimped to the cable. Furthermore, the cable lug includes a fastening section connected to the sleeve section. The attachment portion is plate-shaped or disc-shaped. The fastening section can have an opening or a bore. The fastening section can, for example, be screwed or riveted to the press-in element.

According to a further embodiment, the connection arrangement also includes a screw for screwing the cable lug to the press-in element, the screw being accommodated at least in sections in the opening of the press-in element.

For this purpose, the press-in element can have an opening in the middle, which has an internal thread for the screw. For example, the internal thread is an M2 thread. The breakthrough is preferably a through hole. A screw connection can also be provided. In this case, a nut is required for the screw.

According to a further embodiment, the connection arrangement also comprises a washer which is arranged between a screw head of the screw and a fastening section of the cable lug.

In addition to the screw head, the screw includes a threaded bolt. The threaded bolt is passed through the above-mentioned opening in the fastening section of the cable lug and is screwed to the press-in element. The washer ensures an even distribution of force from the screw head to the fastening section of the cable lug.

According to a further embodiment, the metal sleeve is made of copper, in particular coated with gold, silver or tin.

Electroless gold uses a layer of nickel between the copper and the gold. The gold, silver or tin can be galvanically deposited on the metal sleeve. The metal sleeve can also be referred to as a copper sleeve.

According to a further embodiment, the press-in element is made of brass, in particular coated with gold, silver or tin.

Bronze can also be used as the material for the press-fit element. The gold, silver or tin can be electroplated on the press-in element.

Furthermore, a projection exposure system with at least one such connection arrangement is proposed.

The projection exposure system can include any number of such connection arrangements. The projection exposure system can be an EUV lithography system. EUV stands for "Extreme Ultraviolet" and designates a working light wavelength between 0.1 nm and 30 nm. The projection exposure system can also be a DUV lithography system. DUV stands for "Deep Ultraviolet" and describes a working light wavelength between 30 nm and 250 nm.

In addition, a method for producing a connection arrangement for the solderless and electrically conductive connection of a press-in element to a printed circuit board is proposed. The method comprises the following steps: a) providing a metal sleeve provided at an opening in the printed circuit board, b) providing the press-in element, and c) pressing a press-in section of the press-in element into the metal sleeve in such a way that the press-in section is cold-welded to the metal sleeve, the press-in element comprises an opening for establishing an electrical connection with the press-in element, wherein the opening, viewed along an axis of symmetry of the press-in element, is guided at least into the metal sleeve, so that the electrical connection can be established at the level of the metal sleeve, viewed along the axis of symmetry.

Providing the metal sleeve provided at the opening of the printed circuit board can include manufacturing the printed circuit board. In this case, for example, the metal sleeve is galvanically deposited at the opening. Providing the press-in element can include manufacturing the press-in element include. For example, the press-in element is a turned and/or milled part. Due to the tight tolerances, turned and/or milled parts are typically used that are galvanically and/or chemically coated. The pressing of the press-in element into the metal sleeve takes place in particular along the axis of symmetry of the press-in element. The press-in element is pressed under high pressure into the metal sleeve, which is then plastically deformed. The press-in element can also deform plastically. This plastic deformation causes the contact surfaces of the press-in element and the metal sleeve to come very close together. The intensive touching of the two contact surfaces results in a stable connection between the press-in element, in particular the press-in section of the press-in element, and the metal sleeve. In this case, the press-in element is preferably made of brass or bronze, and the metal sleeve is preferably made of copper.

According to one embodiment, after step c), a cable is electrically conductively connected to the opening of the press-in element.

The cable can be clamped, for example, under a screw head of a screw screwed into the press-in element. The cable can also be riveted to the press-in element, for example.

According to a further embodiment, the cable is electrically conductively connected to the opening of the press-in element with the aid of a cable lug.

As previously mentioned, the cable lug includes a barrel portion which is crimped onto the cable. The attachment portion of the cable lug is screwed to the press-in member using the aforementioned screw. The washer is provided between the screw head of the screw and the fastening section of the cable lug. The cable lug can also be riveted to the press-in element. In this case, a rivet is provided instead of the screw.

According to a further embodiment, the press-in portion is polygonal and comprises edges running along the axis of symmetry of the press-in element, only the edges being cold-welded to the metal sleeve.

In particular, the press-in section contacts the metal sleeve only with the aid of the edges. As a result, a high contact pressure can be built up in the area of the edges, which ensures reliable cold welding.

"A" is not necessarily to be understood as being limited to exactly one element. Rather, a plurality of elements, such as two, three or more, can also be provided. Any other count word used here should also not be understood to mean that there is a restriction to precisely the stated number of elements. Rather, numerical deviations upwards and downwards are possible, unless otherwise stated.

The embodiments and features described for the connection arrangement apply correspondingly to the proposed projection exposure system and to the proposed method 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 einen schematischen Meridionalschnitt einer Projektionsbelichtungsanlage für die EUV-Projektionslithographie;
• 2 zeigt eine schematische Explosionsansicht einer Ausführungsform einer Verbindungsanordnung für die Projektionsbelichtungsanlage gemäß 1;
• 3 zeigt eine schematische Aufsicht einer Ausführungsform eines Einpresselements für die Verbindungsanordnung gemäß 2;
• 4 zeigt eine schematische perspektivische Ansicht des Einpresselements gemäß 3;
• 5 zeigt eine schematische Aufsicht der Verbindungsanordnung gemäß 2;
• 6 zeigt eine schematische Aufsicht einer weiteren Ausführungsform eines Einpresselements für die Verbindungsanordnung gemäß 2;
• 7 zeigt eine schematische perspektivische Ansicht des Einpresselements gemäß 6; und
• 8 zeigt ein schematisches Blockdiagramm einer Ausführungsform eines Verfahrens zum Herstellen der Verbindungsanordnung gemäß 2.

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 meridional section of a projection exposure system for EUV projection lithography;
• 2 shows a schematic exploded view of an embodiment of a connection arrangement for the projection exposure apparatus according to FIG 1 ;
• 3 12 shows a schematic plan view of an embodiment of a press-in element for the connection arrangement according to FIG 2 ;
• 4 shows a schematic perspective view of the press-in element according to FIG 3 ;
• 5 shows a schematic top view of the connection arrangement according to FIG 2 ;
• 6 FIG. 12 shows a schematic top view of a further embodiment of a press-in element for the connection arrangement according to FIG 2 ;
• 7 shows a schematic perspective view of the press-in element according to FIG 6 ; and
• 8th shows a schematic block diagram of an embodiment of a method for Making the connection arrangement according to 2 .

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 shows an embodiment of a projection exposure system 1 (lithography system), in particular an EUV lithography system. One embodiment of an illumination system 2 of the projection exposure system 1 has, in addition to a light or radiation source 3, illumination optics 4 for illuminating an object field 5 in an object plane 6. In an alternative embodiment, the light source 3 can also be provided as a separate module from the rest of the illumination system 2. In this case, the lighting system 2 does not include the light source 3 .

A reticle 7 arranged in the object field 5 is exposed. The reticle 7 is held by a reticle holder 8 . The reticle holder 8 can be displaced via a reticle displacement drive 9, in particular in a scanning direction.

In the 1 a Cartesian coordinate system with an x-direction x, a y-direction y and a z-direction z is drawn in for explanation. The x-direction x runs perpendicularly into the plane of the drawing. The y-direction y runs horizontally and the z-direction z runs vertically. The scanning direction is in the 1 along the y-direction y. The z-direction z runs perpendicular to the object plane 6.

The projection exposure system 1 includes projection optics 10. The projection optics 10 are used to image the object field 5 in an image field 11 in an image plane 12. The image plane 12 runs parallel to the object plane 6. Alternatively, there is also an angle other than 0° between the object plane 6 and the Image plane 12 possible.

A structure on the reticle 7 is imaged onto a light-sensitive layer of a wafer 13 arranged in the region of the image field 11 in the image plane 12 . The wafer 13 is held by a wafer holder 14 . The wafer holder 14 can be displaced in particular along the y-direction y via a wafer displacement drive 15 . The displacement of the reticle 7 via the reticle displacement drive 9 on the one hand and the wafer 13 on the other hand via the wafer displacement drive 15 can be synchronized with one another.

The light source 3 is an EUV radiation source. The light source 3 emits in particular EUV radiation 16, which is also referred to below as useful radiation, illumination radiation or illumination light. The useful radiation 16 has in particular a wavelength in the range between 5 nm and 30 nm. The light source 3 can be a plasma source, for example an LPP source (Engl .: Laser Produced Plasma, plasma generated with the help of a laser) or a DPP (Gas Discharged Produced Plasma) source. It can also be a synchrotron-based radiation source. The light source 3 can be a free-electron laser (FEL).

The illumination radiation 16 emanating from the light source 3 is bundled by a collector 17 . The collector 17 can be a collector with one or more ellipsoidal and/or hyperboloidal reflection surfaces. The at least one reflection surface of the collector 17 can in grazing incidence (Engl.: Grazing Incidence, GI), i.e. with angles of incidence greater than 45°, or in normal incidence (Normal Incidence, NI), i.e. with angles of incidence less than 45°, with the Illumination radiation 16 are applied. The collector 17 can be structured and/or coated on the one hand to optimize its reflectivity for the useful radiation and on the other hand to suppress stray light.

After the collector 17, the illumination radiation 16 propagates through an intermediate focus in an intermediate focal plane 18. The intermediate focal plane 18 can represent a separation between a radiation source module, comprising the light source 3 and the collector 17, and the illumination optics 4.

The illumination optics 4 comprises a deflection mirror 19 and a first facet mirror 20 downstream of this in the beam path. The deflection mirror 19 can be a plane deflection mirror or alternatively a mirror with an effect that influences the bundle beyond the pure deflection effect. Alternatively or additionally, the deflection mirror 19 can be designed as a spectral filter, which separates a useful light wavelength of the illumination radiation 16 from stray light of a different wavelength. If the first facet mirror 20 is arranged in a plane of the illumination optics 4 which is optically conjugate to the object plane 6 as the field plane, it is also referred to as a field facet mirror. The first facet mirror 20 includes a large number of individual first facets 21, which can also be referred to as field facets. Of these first facets 21 are in the 1 only a few shown as examples.

The first facets 21 can be embodied as macroscopic facets, in particular as rectangular facets or as facets with an arcuate or part-circular edge contour. The first facets 21 can be embodied as planar facets or alternatively as convexly or concavely curved facets.

Like for example from the DE 10 2008 009 600 A1 is known, the first facets 21 themselves can each also be composed of a large number of individual mirrors, in particular a large number of micromirrors. The first facet mirror 20 can be embodied in particular as a microelectromechanical system (MEMS system). For details refer to the DE 10 2008 009 600 A1 referred.

The illumination radiation 16 runs horizontally between the collector 17 and the deflection mirror 19, ie along the y-direction y.

A second facet mirror 22 is arranged downstream of the first facet mirror 20 in the beam path of the illumination optics 4. If the second facet mirror 22 is arranged in a pupil plane of the illumination optics 4, it is also referred to as a pupil facet mirror. The second facet mirror 22 can also be arranged at a distance from a pupil plane of the illumination optics 4 . In this case, the combination of the first facet mirror 20 and the second facet mirror 22 is also referred to as a specular reflector. Specular reflectors are known from US 2006/0132747 A1 , the EP 1 614 008 B1 and the U.S. 6,573,978 .

The second facet mirror 22 includes a plurality of second facets 23. In the case of a pupil facet mirror, the second facets 23 are also referred to as pupil facets.

The second facets 23 can also be macroscopic facets, which can have round, rectangular or hexagonal borders, for example, or alternatively facets composed of micromirrors. In this regard, also on the DE 10 2008 009 600 A1 referred.

The second facets 23 can have plane or alternatively convexly or concavely curved reflection surfaces.

The illumination optics 4 thus forms a double-faceted system. This basic principle is also known as a honeycomb condenser (English: Fly's Eye Integrator).

It can be advantageous not to arrange the second facet mirror 22 exactly in a plane which is optically conjugate to a pupil plane of the projection optics 10 . In particular, the second facet mirror 22 can be arranged tilted relative to a pupil plane of the projection optics 10, as is the case, for example, in FIG DE 10 2017 220 586 A1 is described.

The individual first facets 21 are imaged in the object field 5 with the aid of the second facet mirror 22 . The second facet mirror 22 is the last beam-forming mirror or actually the last mirror for the illumination radiation 16 in the beam path in front of the object field 5.

In a further embodiment of the illumination optics 4 that is not shown, transmission optics can be arranged in the beam path between the second facet mirror 22 and the object field 5 , which particularly contribute to the imaging of the first facets 21 in the object field 5 . The transmission optics can have exactly one mirror, but alternatively also have two or more mirrors, which are arranged one behind the other in the beam path of the illumination optics 4 . The transmission optics can in particular comprise one or two mirrors for normal incidence (NI mirror, normal incidence mirror) and/or one or two mirrors for grazing incidence (GI mirror, gracing incidence mirror).

The illumination optics 4 has the version in which 1 shown, exactly three mirrors after the collector 17, namely the deflection mirror 19, the first facet mirror 20 and the second facet mirror 22.

In a further embodiment of the illumination optics 4, the deflection mirror 19 can also be omitted, so that the illumination optics 4 can then have exactly two mirrors after the collector 17, namely the first facet mirror 20 and the second facet mirror 22.

The imaging of the first facets 21 by means of the second facets 23 or with the second facets 23 and transmission optics in the object plane 6 is generally only an approximate imaging.

The projection optics 10 includes a plurality of mirrors Mi, which are numbered consecutively according to their arrangement in the beam path of the projection exposure system 1 .

At the in the 1 example shown, the projection optics 10 includes six mirrors M1 to M6. Alternatives with four, eight, ten, twelve or another number of mirrors Mi are also possible. The projection optics 10 are doubly obscured optics. The penultimate mirror M5 and the last mirror M6 each have a passage opening for the illumination radiation 16. The projection optics 10 has an image-side numerical aperture which is greater than 0.5 and which can also be greater than 0.6 and which, for example, is 0.7 or 0.75.

Reflection surfaces of the mirrors Mi can be designed as free-form surfaces without an axis of rotational symmetry. Alternatively, the reflection surfaces of the mirrors Mi can be designed as aspherical surfaces with exactly one axis of rotational symmetry of the reflection surface shape. Just like the mirrors of the illumination optics 4, the mirrors Mi can have highly reflective coatings for the illumination radiation 16. These coatings can be designed as multilayer coatings, in particular with alternating layers of molybdenum and silicon.

The projection optics 10 has a large object-image offset in the y-direction y between a y-coordinate of a center of the object field 5 and a y-coordinate of the center of the image field 11. This object-image offset in the y-direction y can be about as large as a z-distance between the object plane 6 and the image plane 12.

The projection optics 10 can in particular be anamorphic. In particular, it has different image scales βx, βy in the x and y directions x, y. The two image scales βx, βy of the projection optics 10 are preferably at (βx, βy)=(+/−0.25, /+−0.125). A positive image scale β means an image without image reversal. A negative sign for the imaging scale 6 means imaging with image inversion.

The projection optics 10 thus leads to a reduction in the ratio 4:1 in the x-direction x, ie in the direction perpendicular to the scanning direction.

The projection optics 10 lead to a reduction of 8:1 in the y-direction y, ie in the scanning direction.

Other imaging scales are also possible. Image scales with the same sign and absolutely the same in the x and y directions x, y, for example with absolute values of 0.125 or 0.25, are also possible.

The number of intermediate image planes in the x and y directions x, y in the beam path between the object field 5 and the image field 11 can be the same or, depending on the design of the projection optics 10, can be different. Examples of projection optics with different numbers of such intermediate images in the x and y directions x, y are known from U.S. 2018/0074303 A1 .

In each case one of the second facets 23 is assigned to precisely one of the first facets 21 in order to form a respective illumination channel for illuminating the object field 5 . In this way, in particular, lighting can result according to Köhler's principle. The far field is broken down into a large number of object fields 5 with the aid of the first facets 21 . The first facets 21 generate a plurality of images of the intermediate focus on the second facets 23 assigned to them.

The first facets 21 are each imaged onto the reticle 7 by an associated second facet 23 in a superimposed manner in order to illuminate the object field 5 . In particular, the illumination of the object field 5 is as homogeneous as possible. It preferably has a uniformity error of less than 2%. Field uniformity can be achieved by superimposing different illumination channels.

The illumination of the entrance pupil of the projection optics 10 can be defined geometrically by arranging the second facets 23 . The intensity distribution in the entrance pupil of the projection optics 10 can be set by selecting the illumination channels, in particular the subset of the second facets 23 that guide light. This intensity distribution is also referred to as illumination setting or illumination pupil filling.

A likewise preferred pupil uniformity in the area of defined illuminated sections of an illumination pupil of the illumination optics 4 can be achieved by redistributing the illumination channels.

Further aspects and details of the illumination of the object field 5 and in particular the entrance pupil of the projection optics 10 are described below.

The projection optics 10 can in particular have a homocentric entrance pupil. This can be accessible. It can also be inaccessible.

The entrance pupil of the projection optics 10 can be regularly matched with the second facet mirror gel 22 do not illuminate exactly. When imaging the projection optics 10, which telecentrically images the center of the second facet mirror 22 onto the wafer 13, the aperture rays often do not intersect at a single point. However, a surface can be found in which the distance between the aperture rays, which is determined in pairs, is minimal. This surface represents the entrance pupil or a surface conjugate to it in position space. In particular, this surface shows a finite curvature.

The projection optics 10 may have different positions of the entrance pupil for the tangential and for the sagittal beam path. In this case, an imaging element, in particular an optical component of the transmission optics, should be provided between the second facet mirror 22 and the reticle 7 . With the help of this optical element, the different positions of the tangential entrance pupil and the sagittal entrance pupil can be taken into account.

At the in the 1 shown arrangement of the components of the illumination optics 4, the second facet mirror 22 is arranged in a conjugate to the entrance pupil of the projection optics 10 surface. The first facet mirror 20 is arranged tilted to the object plane 6 . The first facet mirror 20 is tilted relative to an arrangement plane that is defined by the deflection mirror 19 . The first facet mirror 20 is tilted relative to an arrangement plane that is defined by the second facet mirror 22 .

In the projection exposure system 1 it is necessary to wire a wide variety of actuators, sensors, cables and printed circuit boards under EUV conditions. In this case, for example, in the case of an electrical connection between a cable and a printed circuit board, attention must be paid to a small installation space requirement. Due to the EUV conditions, in particular vacuum environment and atmosphere containing hydrogen, only a limited choice of materials is possible. For example, soldered connections are unsuitable.

2 shows a schematic exploded view of a solderless connection arrangement 100 for electrically conductively connecting a cable 102 to a circuit board 104. The circuit board 104 includes a front 106 and a back 108 and an opening 110. The opening 110 can also be referred to as a bore or breakthrough. The circuit board 104 can be any type of non-flexible circuit board. For example, ceramic, glass or FR4 can be used.

A metal sleeve 112 is accommodated in the opening 110 and can be electrically conductively connected, for example, to conductor tracks provided on the printed circuit board 104 . The metal sleeve 112 is a copper sleeve and can also be referred to as such. The metal sleeve 112 is attached to the printed circuit board 104 during its manufacture, for example. The metal sleeve 112 can be electroplated with tin, silver or gold. The metal sleeve 112 itself can also be deposited galvanically (Engl .: Plated Through Hole).

The connection arrangement 100 includes a press-fit element 114 which is press-fitted into the metal sleeve 112 . As a result, the press-in element 114 is cold-welded to the metal sleeve 112 . This is done using massive press-in technology. Cold welded joints or cold pressure welded joints are made under high pressure and, in contrast to other welding methods, below the recrystallization temperature of the individual parts. The two parts remain in the solid state, but plastic deformation is necessary with a close approximation of the contact surfaces. The intensive touching of the two contact surfaces creates a stable connection between the two workpieces.

The press-in element 114 can have a through hole or an internal thread. For example, an internal thread M2 can be used. A screw 116 is screwed into the press-in element 114 . A rivet can also be provided instead of the screw 116 . The screw 116 comprises a disk-shaped screw head 118 and a threaded bolt 120. In principle, any type of screw 116 can be used. In order to achieve the small installation space required here, a screw 116 with a screw head 118 that is as small as possible, in particular as flat as possible, is preferably selected.

A washer 122 and a cable lug 124 are connected to the press-in element 114 with the aid of the screw 116 . The washer 122 is placed between the screw head 118 and the cable lug 124 . The cable lug 124 comprises a plate-shaped fastening section 126 with an opening for the threaded bolt 120 and a sleeve section 128 which is crimped to the cable 102.

The cable lug 124 is electrically conductively and mechanically connected to the press-in element 114 with the aid of the screw 116 . A solder-free electrical connection between the cable 102 and the printed circuit board 104 can thus be established. This results in the smallest possible space requirement above and below the printed circuit board 104 with the lowest possible electrical contact resistance.

3 Figure 12 shows a schematic plan view of an embodiment of a press-in element 114A as mentioned above. 4 12 shows a schematic perspective view of the press-in element 114A. The following will refer to the 3 and 4 referenced at the same time.

The press-in element 114A includes a disk-shaped base portion 130 which rests on the front side 106 of the circuit board 104 . The base section 130 is rotationally symmetrical to a central or symmetrical axis 132 of the press-in element 114A. A block-shaped or cuboid press-in section 134 extends out of the base section 130 on the underside. The press-in portion 134 is rectangular in plan view. However, the press-in section 134 can also have a different geometry, for example a triangular geometry, in the top view.

The press-in section 134 has four edges 136 , 138 , 140 , 142 which run parallel to the axis of symmetry 132 . The edges 136, 138, 140, 142 lie on a common auxiliary circle 144 with a diameter d1. This means in particular that all edges 136, 138, 140, 142 are placed at a distance from the axis of symmetry 132 by half the diameter d1. The diameter d1 of the auxiliary circle 144 is smaller than a diameter of the base section 130.

The press-in section 134 is broken through in the middle by an opening 146 that is rotationally symmetrical to the axis of symmetry 132 . The opening 146 can have an internal thread for the screw 116 . A conical flange 148 can run around the opening 146 and extends out of the press-in section 134 along the axis of symmetry 132 .

5 shows a schematic plan view of the connection arrangement 100. In FIG 5 however, only the press-in portion 134 of the press-in member 114A is shown. The metal sleeve 112 has a cylindrical inner surface 150 which is rotationally symmetrical to the axis of symmetry 132 . The inner surface 150 has an inner diameter d2 that is at least slightly smaller than the diameter d1 of the auxiliary circle 144 of the edges 136,138,140,142.

To connect the press-in element 114A to the metal sleeve 112, the press-in section 134 is pressed into the metal sleeve 112 along the axis of symmetry 132, as in FIG 2 with the help of an arrow 152 is indicated. Because the diameter d1 is larger than the inside diameter d2, the sharp-edged edges 136, 138, 140, 142 deform the metal sleeve 112, as a result of which the edges 136, 138, 140, 142 are cold-welded to the metal sleeve 112. The metal sleeve 112 is thus plastically deformed in the area of the edges 136, 138, 140, 142. The edges 136, 138, 140, 142 can also be plastically deformed. The diameter d1 is selected in such a way that the metal sleeve 112 is not perforated radially. However, slight deformations of the material of the circuit board 104 are permissible.

The press-in element 114A is preferably a one-piece component, in particular a component made of one piece of material. In the present case, “in one piece” or “in one piece” means that the press-in element 114A is not formed from different components, but forms one component. In the present case, “in one piece” means that the press-in element 114A is made of the same material throughout. Preferably, the press-in element 114A is made of brass or bronze. The press-in element 114A can be electroplated with gold, silver or tin.

6 Figure 12 shows a schematic plan view of another embodiment of a press-in element 114B as mentioned above. 7 12 shows a schematic perspective view of the press-in element 114B. The following will refer to the 6 and 7 referenced at the same time.

The press-in element 114B differs from the press-in element 114A only by an alternative configuration of the press-in section 134. The press-in section 134 of the press-in element 114B is not square but polygonal, in particular star-shaped. For example, the press-in portion 134 has twenty-four sharp edges 154, of which 6 and 7 only one is provided with a reference number.

The number of edges 154 is arbitrary. The edges 154 run parallel to the axis of symmetry 132. The press-in section 134 can be referred to as knurled or knurled. The geometry of the press-in section 134 with the multiplicity of edges 154 can enable a smaller diameter of the opening 110 of the circuit board 104 or a smaller inner diameter d2 of the metal sleeve 112 . The function of the press-in element 114B corresponds to that of the press-in element 114A.

In both press-in elements 114A, 114B, the opening 146 can also be a through hole without an internal thread. In this case, a bolt-through connection with a lock nut for fastening the cable lug 124 and the washer 122 can be provided. A rivet connection can also be used.

The connection arrangement 100 can connect a plurality of cable lugs 124 and thus a plurality of cables 102 with a metal sleeve 112 . Two printed circuit boards 104 can be electrically and mechanically connected to one another. Furthermore, attachment of other components, such as a fan, is also possible.

The opening 146 serves to establish an electrical connection with the press-in element 114A, 114B. For this purpose, opening 146 is routed at least into metal sleeve 112, viewed along axis of symmetry 132 of press-in element 114A, 114B, so that the electrical connection can be made at the level of metal sleeve 112, viewed along axis of symmetry 132. This means that the electrical connection is arranged inside the metal sleeve 112 viewed along the axis of symmetry 132 .

8th 12 shows a schematic block diagram of an embodiment of a method for producing the connection arrangement 100. In the method, the metal sleeve 112 provided at the opening 110 of the printed circuit board 104 is provided in a step S1. Step S1 can also include providing the printed circuit board 104 per se.

In a step S2, the press-in element 114A, 114B is provided. Providing can include manufacturing the press-in element 114A, 114B. In a step S3, the press-in element 114A, 114B is pressed into the metal sleeve 112 in such a way that the press-in section 134 of the press-in element 114A, 114B is cold-welded to the metal sleeve 112. In particular, only the edges 136, 138, 140, 142, 154 are cold-welded to the metal sleeve 112.

After step S3, the cable 102 can be electrically conductively connected to the press-in element 114A, 114B, in particular to the opening 146. In this case, the cable 102 can be electrically conductively connected to the press-in element 114A, 114B with the aid of the cable lug 124 .

Although the present invention has been described using exemplary embodiments, it can be modified in many ways.

Reference List

1

projection exposure system

2

lighting system

3

light source

4

lighting optics

5

object field

6

object level

7

reticle

8th

reticle holder

9

reticle displacement drive

10

projection optics

11

image field

12

picture plane

13

wafers

14

wafer holder

15

Wafer displacement drive

16

illumination radiation

17

collector

18

intermediate focal plane

19

deflection mirror

20

first facet mirror

21

first facet

22

second facet mirror

23

second facet

100

connection arrangement

102

Cable

104

circuit board

106

front

108

back

110

opening

112

metal sleeve

114

press-in element

114A

press-in element

114B

press-in element

116

screw

118

screw head

120

threaded bolt

122

washer

124

cable lug

126

attachment section

128

sleeve section

130

base section

132

axis of symmetry

134

press-in section

136

edge

138

edge

140

edge

142

edge

144

auxiliary group

146

breakthrough

148

flange

150

Inner surface

152

Arrow

154

edge

d1

diameter

d2

inner diameter

M1

mirror

M2

mirror

M3

mirror

M4

mirror

M5

mirror

M6

mirror

S1

Step

S2

Step

S3

Step

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 102008009600 A1 [0055, 0059]
• US 2006/0132747 A1 [0057]
• EP 1614008 B1 [0057]
• US6573978 [0057]
• DE 102017220586 A1 [0062]
• US 2018/0074303 A1 [0076]

Claims (15)

Connecting arrangement (100) for the solderless and electrically conductive connection of a press-in element (114A, 114B) to a printed circuit board (104). a metal shell (112) provided at an opening (110) of the circuit board (104), and the press-in member (114A, 114B) having a press-in section (134) press-fitted into the metal shell (112) such that the press-in section (134) is cold-welded to the metal shell (112), and an aperture (146) for making a electrical connection to the press-in element (114A, 114B), wherein the opening (146), viewed along an axis of symmetry (132) of the press-in element (114A, 114B), is guided at least into the metal sleeve (112), so that the electrical connection along the Axis of symmetry (132) viewed at the level of the metal sleeve (112) can be produced. connection arrangement claim 1 , wherein the press-in section (134) is polygonal and comprises edges (136, 138, 140, 142, 154) running along the axis of symmetry (132) of the press-in element (114A, 114B), only the edges (136, 138, 140, 142, 154) are cold welded to the metal sleeve (112). connection arrangement claim 2 , wherein the edges (136, 138, 140, 142, 154) lie on a common auxiliary circle (144), and wherein a diameter (d1) of the auxiliary circle (144) is greater than an inner diameter (d2) of the metal sleeve (112). connection arrangement claim 2 or 3 , wherein the press-in section (134) viewed along the axis of symmetry (132) is square or star-shaped. Connection arrangement according to one of Claims 1 - 4 , wherein the connecting arrangement (100) has the smallest possible installation space as viewed through the pressing of the press-in section (134) into the metal sleeve (112) along the axis of symmetry (132). Connection arrangement according to one of Claims 1 - 5 , further comprising a cable lug (124) for receiving a cable (102), wherein the cable lug (124) is electrically conductively connected to the opening (146) of the press-in element (114A, 114B). connection arrangement claim 6 , further comprising a screw (116) for screwing the cable lug (124) to the press-in element (114A, 114B), the screw (116) being accommodated at least in sections in the opening (146) of the press-in element (114A, 114B). connection arrangement claim 7 , further comprising a washer (122) which is arranged between a screw head (118) of the screw (116) and a fastening portion (126) of the cable lug (124). Connection arrangement according to one of Claims 1 - 8th , wherein the metal sleeve (112) is made of copper, in particular coated with gold, silver or tin. Connection arrangement according to one of Claims 1 - 9 , wherein the press-in element (114A, 114B) is made of brass, in particular coated with gold, silver or tin. Projection exposure system (1) with at least one connection arrangement according to one of Claims 1 - 10 . Method for producing a connection arrangement (100) for the solderless and electrically conductive connection of a press-in element (114A, 114B) to a printed circuit board (104), with the following steps: a) providing (S1) a metal sleeve (112) provided at an opening (110) of the printed circuit board (104), b) providing (S2) the press-in element (114A, 114B), and c) pressing (S3) a press-in section (134) of the press-in element (114A, 114B) into the metal sleeve (112) in such a way that the press-in section (134) is cold-welded to the metal sleeve (112), the press-in element (114A, 114B) having a Breakthrough (146) for establishing an electrical connection with the press-in element (114A, 114B), wherein the break-through (146) viewed along an axis of symmetry (132) of the press-in element (114A, 114B) is guided at least into the metal sleeve (112), so that the electrical connection can be established along the axis of symmetry (132) at the level of the metal sleeve (112). procedure after claim 12 , wherein after step c) a cable (102) is electrically conductively connected to the opening (146) of the press-in element (114A, 114B). procedure after Claim 13 , wherein the cable (102) is electrically conductively connected to the opening (146) of the press-in element (114A, 114B) with the aid of a cable lug (124). Procedure according to one of Claims 12 - 14 , wherein the press-in section (134) is polygonal and comprises edges (136, 138, 140, 142, 154) running along the axis of symmetry (132) of the press-in element (114A, 114B), only the edges (136, 138, 140, 142, 154) are cold-welded to the metal sleeve (112).

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