DE102022211559A1 - Contacting an electrical component in an optical element - Google Patents

Abstract

The invention relates to an optical element (100) for a microlithographic projection exposure system, having a body (101) onto which at least a first conductor track (102) and a second conductor track (103) are applied or introduced, and having at least one electrical component (107) , characterized in that the at least one electrical component (107) has a first electrical contact surface (105) and a second electrical contact surface (106) spaced apart from the first electrical contact surface (105), that the electrical component (107) with the electrical conductor tracks (102,103) is electrically conductively connected by means of an electrically conductive adhesive applied over a surface or in a structured manner in such a way that the first electrical contact surface (105) is electrically conductive with the first conductor track (102) and the second electrical contact surface (106) with the second conductor track (103). are connected, and the first electrical contact surface (105) and the second electrical contact surface (106) are electrically insulated from one another.

Description

The invention relates to an optical element, in particular an adaptive mirror, for a microlithographic projection exposure system, having a body on which at least a first conductor track and a second conductor track are applied or introduced, and having at least one electrical component.

Projection exposure systems are used to produce extremely fine structures, in particular on semiconductor components or other microstructured components. The functional principle of the systems mentioned is based on generating the finest structures down to the nanometer range by means of a generally reduced image of structures on a mask, a so-called reticle, on an element to be structured provided with photosensitive material, a so-called wafer. The minimum dimensions of the structures produced depend directly on the wavelength of the light used. This is formed in an illumination optics for optimal illumination of the reticle. Recently, light sources with an emission wavelength in the range of a few nanometers, for example between 1 nm and 120 nm, in particular in the range of 13.5 nm, have been increasingly used. The wavelength range described is also referred to as the EUV range.

In addition to systems working in the EUV range, the microstructured components are also manufactured using the DUV systems established on the market with a wavelength between 100 nm and 300 nm, in particular 193 nm. With the requirement to be able to produce ever smaller structures, the requirements for the optical correction in the systems have increased further.

In projection lenses designed for the EUV range, i.e. at wavelengths of around 13 nm or around 7 nm, for example, mirrors are used as optical components for the imaging process due to the lack of availability of suitable transparent refractive materials.

Optical elements such as lenses or adaptive mirrors usually have a body that is connected to at least one electrical component, such as a sensor, a temperature control element or an actuator. In order to be able to connect these electrical components to a voltage source and, if necessary, to control them separately or to be able to contact them separately, a line must be routed between the electrical components to a transfer point of the optical element to the outside. Furthermore, the electrical lines must make contact with the electrical element. In the case of optical elements in which the electrical components are located in a cavity, it is also challenging to route the electrical lines out of this cavity.

It is known from the prior art to contact the electrical components by means of cables, with an increasing number of electrical components--in particular with an increasing number of actuators, sensors and temperature control elements--a large number of cables being required, which accordingly have a large installation space requirement . In addition, this high number of cables can represent a vibrating mass. This can have an adverse effect on the controllability of the optical element. The cable routing on the optical element must also be fixed at several points, which represents additional effort and can also have a negative effect on the effective optical surface.

Cables that are not sufficiently mechanically secured or that are routed outside of the optical element also pose an increased risk of damage in the manufacturing process of the optical element, since they can tear off or mechanically damage the body of the optical element. In addition, a fluid-tight and/or gas-tight passage of the cable through a component represents an increased manufacturing effort. Likewise, a clear assignment of the cable is necessary to prevent incorrect activation of the electrical components, which is associated with high demands on the manufacturing process.

the WO 2022/023313 A1 discloses structured conductor tracks for contacting electrostrictive actuators and sensors.

In order to control and regulate the at least one electrical component and the optical element itself, the contact between the electrical components and the conductor track is crucial. At the same time, short circuits between the contacts of an electrical component must be prevented.

It is therefore the object of the present invention to provide an optical element which reduces the abovementioned disadvantages.

The object is achieved by an optical element according to claim 1. Advantageous configurations with expedient developments are specified in the dependent claims.

The optical element is characterized in that the electrical component, a first having an electrical contact surface and a second electrical contact surface spaced apart from the first electrical contact surface. The electrical component is electrically conductively connected to the electrical conductor tracks by means of an electrically conductive adhesive applied over a surface or pattern in such a way that the first electrical contact area is electrically conductively connected to the first conductor track and the second electrical contact area is electrically conductively connected to the second conductor track, with the first electrical contact area and the second electrical contact area are electrically isolated from each other.

The electrically conductive adhesive applied in a planar or structured manner enables contact to be made between the first electrical contact surface and the first conductor track and between the second electrical contact surface and the second conductor track, without a short circuit occurring as a result of an electrical connection between the first electrical contact surface and the second electrical contact surface comes.

The optical element can preferably be an adaptive mirror or a lens or a supporting structure of the optical element, in particular a mirror frame or a force-transmitting frame of the optical element, or a sensor frame.

The conductor tracks are preferably applied or incorporated in a joint plane of the optical element and the electrical component. The conductor tracks can also be formed on a conductor track board, which in one embodiment is provided between the outer joining points of the electrical component and a further electrical component.

The circuit board is preferably made from the same material as the optical element, in particular from a mirror material such as quartz glass or titanium silicate glass. Alternatively, the printed circuit board can also be formed from the same material as the electrical component.

The circuit board preferably has conductor tracks on both sides. In this case, the conductor tracks of the two sides of the circuit board can preferably be connected by means of electrical through-contacting. The circuit boards can also be designed as flexible circuit boards, in particular as flexible PCB boards. In addition to the conductor path routing to the respective electrical component, additional functions such as the routing of further electrical conductor paths for further electrical components such as temperature sensors or strain sensors can preferably be provided. In addition, the circuit boards can preferably also include functional elements such as sensors, in particular expansion sensors, temperature sensors and position sensors, which are applied by coating and structuring.

The conductor tracks can be applied using different manufacturing processes. These include in particular the structured coating, for example using photolithographic methods, the structuring of homogeneous coatings using etching methods or laser-based methods such as laser ablation. Mask-based processes or the application of the conductor tracks using electrically conductive inks can also be used. The electrically conductive inks (varnishes) can be applied using standard printing processes. These include in particular piezojetting (inkjet), screen printing, stencil printing and microdosing. The conductor tracks can be single-layer or multi-layer; in the case of a single-layer structure, the conductor tracks can be implemented with or without an electrical insulating layer. The electrically insulating layer is preferably formed from a material having a high electrical resistivity. For example, from Al ₂ O ₃ or SiO ₂ , as well as from organic materials. In one embodiment, the conductor tracks are arranged exclusively on those surfaces of the body that are formed between the electrical components. Alternatively, the conductor tracks can also be routed under the electrical components, or can be routed through the body.

In this case, the first electrical contact surface and the second electrical contact surface can have a raised structure which improves electrical contacting between the contact surface and the conductor track assigned to it.

In a preferred embodiment, the electrically conductive adhesive is formed as an anisotropically electrically conductive adhesive. The anisotropically electrically conductive adhesive can include electrically conductive elements such as metal balls (e.g. silver or platinum), which are spaced apart from one another in such a way that when the electrical component is joined to the conductor track, the electrically conductive elements of the adhesive in the area of the (preferably raised) electrical Contact surfaces to each other, as well as to the electrical contact surfaces and the conductor tracks. In contrast, the electrically conductive elements do not touch in the area formed between the first contact surface and the second contact surface, ie an insulating surface, so that the first electrical contact surface and the second electrical contact surface are electrically insulated from one another. The anisotropic adhesive can be based on resin (single-component or multi-component), in particular based on epoxy resin or acrylic resin base. It is usually reaction-hardening. Alternatively, the anisotropic adhesive can be based on a thermoplastic, which is generally applied under the influence of temperature.

Alternatively, it is advantageous if a contact area having an electrically conductive adhesive is formed between the first electrical contact area and the first conductor track and between the second electrical contact area and the second conductor track, which is set up to connect the first electrical contact area with the first conductor track and the to electrically connect the second electrical contact surface of the second conductor track, and if an insulating surface is formed between the first electrical contact surface and the second electrical contact surface, which is set up to prevent an electrical connection between one of the electrical contact surfaces and the second electrical contact surface.

It is thus preferred in one embodiment if the electrically conductive adhesive is applied exclusively to the electrical contact surfaces. The contacting between the conductor tracks and the electrical contact areas is therefore preferably carried out areally by means of an electrically conductive adhesive, with the insulating areas between the electrical contact areas being free of electrically conductive adhesive.

Alternatively, it is preferred if an insulating surface is formed between the first electrical contact surface and the second electrical contact surface, and if an electrically non-conductive adhesive, ie an electrically insulating adhesive, is applied to the insulating surface. This improves the adhesion of the electrical component to the body while preventing a short circuit.

Furthermore, it is alternatively possible that the structured application of the adhesive comprises at least a first segment with a plurality of spaced-apart first adhesive points of an electrically conductive adhesive and a second segment with a plurality of second adhesive points of an electrically conductive adhesive, and that the first segment and the second segment are spaced from each other such that electrical connection between the electrical contact pads is prevented, that the electrical contact pads are isolated from each other. The segments can be formed both on the electrical contact surfaces and on the insulating surface, with a short circuit between the electrical contact surfaces being prevented due to the spacing of the segments from one another. As a result of the segmentation and the structured, in particular selective application of the adhesive, the adhesion between the electrical component and the body is thus improved and at the same time a short circuit is prevented.

In this context, it is also advantageous if a first center distance between the first adhesive points is smaller than a second center distance between a first adhesive point of the first segment arranged on the edge and a second adhesive point on the edge of a second segment adjacent to the first segment and facing this first adhesive point. In other words, the distances between the first adhesive points are smaller than the edge-side distance between the first segment and the second segment. This enables high electrical conductivity between the first conductor track and the first electrical contact area and the second conductor track and the second electrical contact area, while avoiding a short circuit between the first and the second electrical contact area.

In particular, it is provided that the at least one electrical component is formed as an actuator, in particular as a solid-state actuator. The solid-state actuator can be formed from piezostrictive, electrostrictive, photostrictive or magnetostrictive material. Alternatively, the actuator can also be designed as a thermal actuator with a heating element, or as an electrostatic actuator, or as a magnetic actuator.

In particular, it is preferred if a plurality of electrical components are present, with the electrical components being in the form of actuators. In this case, each actuator can have a first electrical contact surface and at least one second electrical contact surface, the electrical contact surfaces being electrically connectable or connected to the first conductor track or the second conductor tracks by means of an electrically conductive adhesive applied in a planar or structured manner. In this case, the actuator can comprise a plurality of separately controllable areas. Furthermore, the actuator areas can have internal contacts so that they are at a common electrical potential. This allows the number of electrical contact points to be reduced. One of the conductor tracks or both conductor tracks can also lead to a voltage source and can also be connected to a voltage source via an electrically conductive adhesive. The actuators or the electrical components can be controlled separately or together. Correspondingly, further conductor tracks can also be present.

Alternatively or additionally, the at least one electrical component can be formed as a sensor, in particular as a temperature sensor or as a strain sensor.

Furthermore, it is alternatively or additionally advantageous if the at least one electrical component is formed as a temperature control element, in particular as a heating element or as a cooling element. This enables temperature control of the optical element.

Furthermore, it is advantageous if a number of different electrical components are present. The optical element can have actuators and/or sensors and/or temperature control elements, which are electrically connected to a voltage source via different or common conductor tracks, with the contacting between the respective electrical contact surfaces and the conductor track assigned to it being made by means of an electrically conductive adhesive or by means of a structured application of the electrically conductive adhesive takes place.

In this context it is particularly advantageous if each electrical component has at least one further electrical contact surface in addition to the first electrical contact surface and the second electrical contact surface. This enables the further electrical contact surfaces to be electrically connected to further conductor tracks by means of an electrically conductive adhesive applied over a surface area or in a structured manner, so that the electrical components can be controlled separately or together. The electrical components can also be electrically connected or connectable to a further electrical component directly via such a further contact surface. Due to the presence of several contact surfaces, redundant contacting is possible, i. H. if the electrical connection between a contact surface and the associated conductor track fails, it can be replaced by the additional contact surface. Alternatively, due to the presence of different contact surfaces, several separately controllable actuator areas, in particular travel areas (long stroke, short stroke), can be implemented. The actuator can also be formed as an actuator surface composite with a plurality of actuator areas that can be controlled separately and are preferably arranged adjacent to one another.

Furthermore, it is preferred if the first electrical contact surface and the second electrical contact surface are both arranged at a distance from one another on one of the surfaces of the electrical component that faces the body. Alternatively, it is also possible for the first electrical contact surface and the second electrical contact surface to be arranged on different surfaces of the electrical component. In particular, the electrical contact surfaces can be arranged on opposite surfaces of the electrical component.

The optical element is very particularly preferably formed as an adaptive mirror, the body comprising a mirror substrate or the body comprising a mirror substrate and a backplate, the at least one electrical component being connected to the mirror substrate and/or the backplate. The adaptive mirror also has a reflection layer system on the side of the mirror substrate facing away from the rear plate and an active optical surface for exposure to electromagnetic radiation. In addition, a plurality of actuators are preferably provided between the mirror substrate and the rear plate, which allow a deformation of the mirror substrate and thus the optical effective surface. In this context it is particularly preferred if the at least one electrical component of the adaptive mirror is formed as an actuator. Alternatively or additionally, however, the at least one electrical component or further electrical components can also be formed as a sensor and/or as a temperature control element. The conductor tracks can be applied to the top side of the back plate facing the actuator (electrical components) and to the back side of the mirror substrate facing the actuators (electrical components).

The at least one electrical component can be fixed to the body exclusively via the electrically conductive adhesive, or by means of the combination of the electrically conductive adhesive and an electrically non-conductive adhesive. Alternatively, however, additional joining means can also be provided.

Alternatively, optical elements, in particular adaptive mirrors, can also be designed in such a way that a cavity or pocket is formed, in which the at least one electrical component is arranged. This form of the optical elements poses a particular challenge in terms of contacting the electrical component(s). The body has a mirror substrate and a backplate connected to the mirror substrate, with a cavity being formed between the mirror substrate and the backplate. At least one electrical component, in particular an actuator or a sensor or a temperature control element, is provided within the cavity. The conductor tracks can be applied to the backplate or to the mirror substrate. The contact is made by means of an electrically conductive adhesive as previously described. The conductor tracks are brought out outside of the optical element to a voltage source or to an interface, in particular to a plug connection or a cable or a circuit board, analogous to the previously described contacting of the electrical component with the conductor track by means of adhesive bonding by a flat or structured application of an electrically conductive adhesive.

Alternatively, it is also possible for the electrical contact surface and the conductor track to be contacted by means of a solder, with the solder preferably being applied to the electrical contact surfaces and then producing a contact in the joining process of the electrical component with the body by remelting it. The heat can be introduced by heating in an oven or by equipping the electrical contact surfaces with heating elements, in particular ohmic resistance heaters, or by heating the electrical contact surfaces using radiation-based methods such as lasers, infrared radiation or microwaves. Alternatively, the soldering material can also be drawn into the joint by means of capillary action.

As an alternative to gluing using an electrically conductive adhesive, electrical contact can also be made using reactive bonding, an exothermic material-locking joining process with an internal energy source.

As an alternative possibility, the electrical components can also have connecting strands instead of electrical contact surfaces, the connecting strands preferably being electrically connected to the conductor track by means of wire bonding or by means of soldering, in particular by means of reflow soldering. It is also possible to use an electrically conductive adhesive.

Apart from gluing and soldering, friction welding, electron beam welding, laser welding and welding processes that allow energy to be introduced into the joints in a very locally restricted manner are also possible. The connecting strands can preferably be designed as a cable or as an intermediate element between the electrical component and the conductor track. In this case, the intermediate element can be designed, for example, as a circuit board, in particular as a printed circuit board (PCB) and particularly preferably as a flexible printed circuit board.

• 1a eine schematische Darstellung einer für den Betrieb im EUV ausgelegten mikrolithographischen Projektionsbelichtungsanlage,
• 1 b eine schematische Darstellung einer für den Betrieb im DUV ausgelegten mikrolithographischen Projektionsbelichtungsanlage,
• 2 eine schematische Darstellung des Aufbaus eines als ein adaptiver Spiegel gebildeten ersten optischen Elements,
• 3 eine schematische Darstellung der elektrischen Kontaktflächen einer elektrischen Komponente,
• 4 eine schematische Darstellung des Aufbaus eines als ein adaptiver Spiegel gebildeten zweiten optischen Elements,
• 5 ein Schnitt IV-IV der 4,
• 6 eine schematische Darstellung des Aufbaus eines als ein adaptiver Spiegel gebildeten dritten optischen Elements mit gegenüberliegenden elektrischen Kontaktflächen,
• 7 ein Schnitt VI-VI der 5,
• 8 eine schematische Darstellung des Aufbaus eines als ein adaptiver Spiegel gebildeten vierten optischen Elements mit strukturiert aufgetragenem elektrisch leitfähigem Klebstoff,
• 9 ein Detail A der 8,
• 10 ein Schnitt VIII-VIII der 8, und
• 11 eine schematische Darstellung des Aufbaus eines als ein adaptiver Spiegel gebildeten fünften optischen Elements.

Further features, properties and advantages of the present invention are described in more detail below on the basis of embodiment variants with reference to the attached figures. All of the features described above and below are advantageous both individually and in any combination with one another. The embodiment variants described below merely represent examples which, however, do not limit the subject matter of the invention. show:

• 1a a schematic representation of a microlithographic projection exposure system designed for operation in EUV,
• 1 b a schematic representation of a microlithographic projection exposure system designed for operation in the DUV,
• 2 a schematic representation of the structure of a first optical element formed as an adaptive mirror,
• 3 a schematic representation of the electrical contact surfaces of an electrical component,
• 4 a schematic representation of the structure of a second optical element formed as an adaptive mirror,
• 5 a cut IV-IV of the 4 ,
• 6 a schematic representation of the structure of a third optical element formed as an adaptive mirror with opposite electrical contact surfaces,
• 7 a cut VI-VI of the 5 ,
• 8th a schematic representation of the structure of a fourth optical element formed as an adaptive mirror with structured applied electrically conductive adhesive,
• 9 a detail A the 8th ,
• 10 a section VIII-VIII of the 8th , and
• 11 a schematic representation of the structure of a formed as an adaptive mirror fifth optical element.

1a shows a schematic representation of an exemplary projection exposure system 600 designed for operation in the EUV, in which the present invention can be implemented, that is to say in which the actuator 100 according to the invention can be used. However, the invention can also be used in other nanopositioning systems.

According to 1a an illumination device in a projection exposure system 600 designed for EUV has a field facet mirror 603 and a pupil facet mirror 604 . The light from a light source unit, which comprises a plasma light source 601 and a collector mirror 602, is directed onto the field facet mirror 603. In the light path after the pupil facet mirror 604 are a first telescope mirror 605 and a second telescope mirror 606 are arranged. A deflection mirror 607 is arranged downstream in the light path, which deflects the radiation striking it onto an object field in the object plane of a projection objective comprising six mirrors 651-656. At the location of the object field, a reflective structure-bearing mask 621 is arranged on a mask table 620, which is imaged with the aid of the projection lens in an image plane in which a substrate 661 coated with a light-sensitive layer (photoresist) is located on a wafer table 660.

The invention can also be used in a DUV system, as in 1b shown. In principle, a DUV system is like the EUV system described above 1a constructed, whereby mirrors and lenses can be used as optical elements in a DUV system and the light source of a DUV system emits useful radiation in a wavelength range from 100 nm to 300 nm.

In the 1b The DUV lithography system 700 shown has a DUV light source 701 . An ArF excimer laser, for example, can be provided as the DUV light source 701, which emits radiation 702 in the DUV range at, for example, 193 nm. A beam shaping and illumination system 703 directs the DUV radiation 702 onto a photomask 704. The photomask 704 is designed as a transmissive optical element and can be arranged outside of the systems 703. The photomask 704 has a structure which is imaged on a wafer 706 or the like in reduced form by means of the projection system 705 . The projection system 705 has a plurality of lenses 707 and/or mirrors 708 for imaging the photomask 704 onto the wafer 706. In this case, individual lenses 707 and/or mirrors 708 of the projection system 705 can be arranged symmetrically to the optical axis 709 of the projection system 705. It should be noted that the number of lenses 707 and mirrors 708 of the DUV lithography tool 700 is not limited to the number shown. More or fewer lenses 707 and/or mirrors 708 can also be provided. In particular, the beam shaping and illumination system 703 of the DUV lithography system 700 has a plurality of lenses 707 and/or mirrors 708. Furthermore, the mirrors are usually curved on their front side for beam shaping. An air gap 710 between the last lens 707 and the wafer 706 can be replaced by a liquid medium which has a refractive index>1. The liquid medium can be, for example, ultrapure water. Such a structure is also referred to as immersion lithography and has an increased photolithographic resolution. The actuators according to the invention can be used to adjust the lenses 707 and/or mirrors 708 and/or to deform them in the DUV lithography system 700, in particular in its projection system 705.

2 shows a schematic representation of a structure of a first optical element 100 formed as an adaptive mirror 200. The optical element 100 comprises a body 101 formed from a mirror substrate 115 and a back plate 116. FIG. A plurality of electrical components 107 are arranged between the mirror substrate 115 and the back plate 116, which in the present case are in the form of actuators. By acting on the actuators, which can preferably be formed as solid-state actuators, but also as electrostatic or magnetic actuators, the mirror substrate 115 and thus the optical active surface 117 are deformed. In order to be able to control the electrical components 107, in particular the actuators, these must connected to a voltage source. The body 101, in this case the back plate 116, has a first conductor track 102 and a second conductor track 103 for this purpose. The electrical components 107 in turn have at least a first electrical contact surface 105 and - in the 3 shown in more detail - second electrical contact surface 106 on. The electrical component 107 is electrically connected to the first conductor track 102 via the first electrical contact area 105 and to the second conductor track 103 via the second electrical contact area 106, the contacting being effected by means of a planar or structured application of an electrically conductive adhesive. The conductor tracks 102, 103 are in turn connected to a cable 114, which leads to a voltage source, not shown in detail.

3 shows by way of example that the contact is made by applying an anisotropically electrically conductive adhesive, preferably to the electrical contact surfaces 105, 106 and the insulating surfaces 109 formed between the electrical contact surfaces 105, 106. The anisotropically electrically conductive adhesive can include electrically conductive elements such as metal balls (e.g. silver or platinum), which are spaced apart from one another in such a way that when the electrical component 107 is joined to the conductor track 102, 103, the electrically conductive elements of the adhesive in the region of ( preferably raised) electrical contact surfaces 105, 106 to each other, as well as to the electrical contact surfaces 105, 106 and the conductor tracks 102, 103 contact. In contrast, the electrically conductive elements do not touch in the area formed between the first contact surface 105 and the second contact surface 106, i.e. the insulating surface 109, so that the first electrical contact surface 105 and the second electrical contact surface 106 are electrically insulated from one another. Alternatively, the contact can also be made by applying an electrically conductive adhesive exclusively to the electrical contact surfaces 105, 106. In order to also improve the adhesion between the electrical component 107 and the body 101, an electrically non-conductive adhesive, ie an electrically insulating adhesive, can also be applied to the insulating surface 109.

4 12 shows a schematic representation of a second optical element 100 formed as an adaptive mirror, with the body 101 formed as a backplate 116 and a mirror substrate 115. FIG. An electrical component 107 is arranged between the mirror substrate 115 and the backplate 116 and is connected to the backplate 116 and the mirror substrate 115 . In this case, the electrical component 107 has a first electrical contact surface 105 and a second electrical contact surface 106 as well as a first conductor track 102 and a second conductor track 103 . The first electrical contact surface 105 and the second electrical contact surface 106 are both arranged at a distance from one another on a surface of the electrical component 107 that faces the body 101 (here the back plate 116).

Alternatively, the electrical contact surfaces 105, 106 can also be arranged on the surface of the electrical component 107 facing the mirror substrate 115. The conductor tracks 102, 103 are applied to the back plate 116, but can of course also be arranged or applied to the mirror substrate if the electrical contact areas 105, 106 are arranged on the surface of the optical component 107 facing the mirror substrate 116.

5 shows the section of the optical element 100 of FIG 4 and discloses that the first electrical contact surface 105 and the second electrical contact surface 106 are arranged on the same side, ie on the same surface of the electrical component 107.

In contrast, shows 6 an embodiment in which the first electrical contact surface 105 and the second electrical contact surface 106, and the first conductor track 102 and the second conductor track 103 are arranged on different surfaces or sides, in particular on opposite sides of the electrical component 107. This prevents a short circuit, with the contacting between the conductor tracks and the electrical contact surface using an electrically conductive adhesive as before 2 until 4 described, done.

7 shows the section VI-VI of the 6 and with the fact that the first electrical contact areas 105 and the second electrical contact area 106 are arranged on different, namely opposite sides of the electrical component 107 .

the 8th until 10 disclose an embodiment of the optical element 100 or of the adaptive mirror 200, in which the contact is made by an electrically conductive adhesive applied in a structured manner. In particular, the detail A in the 9 and the section VIII-VIII of the 8th in the 10 that the structured application comprises at least a first segment 110 with a plurality of spaced-apart first adhesive points 111 of an electrically conductive adhesive and a second segment 112 with a plurality of second adhesive points 113 of an electrically conductive adhesive. The first segment 110 and the second segment 112 are spaced apart from one another in such a way that an electrical connection between the electrical contact surfaces 105, 106 is prevented. The adhesive points are thus applied both to the electrical contact surfaces 105, 106 and to the insulating surface 109 between the electrical contact surfaces, so that the adhesion between the electrical component 107 and the body 101 is improved.

In an embodiment that is easy to implement, the first segment 110 is assigned to the first electrical contact surface 105 and the second segment 112 to the second electrical contact surface 106 . In order to enable a good electrical connection between conductor track 102, 103 and the electrical contact surface 105, 106 assigned to it and to prevent a short circuit, it is preferred if a first center distance 118 between first adhesive points 111 is smaller than a second center distance 119 between a first adhesive point 111 of the first segment 110 arranged at the edge and a second adhesive point 113 arranged at the edge of a second segment 112 adjacent to the first segment 110 and facing this first adhesive point. The center distance between the first adhesive points is at least 50 μm.

The electrical component 107 is preferably formed as an actuator 104 . Alternatively or additionally—if the optical element 100 comprises a plurality of electrical components 107—the electrical component 107 can also be formed as a sensor (not shown) and/or as a temperature control element (not shown), such as a heating element or a cooling element. In particular, a plurality of different electrical components 107 can be present, in particular actuators, Temperature control element and sensors. In this context, it is advantageous if each electrical component 107 has further electrical contact surfaces in addition to the first electrical contact surface 105 and the second electrical contact surface 106, for example for electrical contacting with a temperature control element or a sensor. In addition, the additional electrical contact surfaces can also be used to enable the actuators to be controlled differently, i.e. in particular to be used as long-stroke actuators and short-stroke actuators with different travel ranges, and for the actuators to have different actuator regions that can be controlled separately from one another. The contacting between the electrical contact surfaces 105, 106 and the conductor tracks 102, 103 takes place via an electrically conductive adhesive applied over a surface area or in a structured manner, as already explained above.

the 11 12 shows a further optical element 100 formed as an adaptive mirror 200, the adaptive mirror being formed as a cavity, ie the mirror substrate 115 forms a cavity with the back plate 116. FIG. Electrical components 107 embodied as actuators 104 are arranged between the rear plate 116 and a mirror substrate rear side 115 . The conductor tracks 102 , 103 are formed on the rear plate or alternatively also on the mirror substrate 115 . At the joint between the mirror substrate 115 and the back plate 116 shown by a circle with a dashed line, the conductor track 102, 103 can be led out of the cavity and connected to a cable, not shown, or a circuit board or a plug connection.

Reference List

100

optical element

101

Body

102

first track

103

second track

104

actuator

105

first contact surface

106

second contact surface

107

electrical component

109

insulating surface

110

first segment

111

first glue points

112

second segment

113

second glue dots

115

mirror substrate

114

Cable

116

backplate

117

optical effective surface

118

first center distance

119

second center distance

200

Adaptive Mirror

600

projection exposure system

601

plasma light source

602

collector mirror

603

field facet mirror

604

pupil facet mirror

605

first telescope mirror

606

second telescope mirror

607

deflection mirror

620

mask table

621

mask

651

mirror (projection lens)

652

mirror (projection lens)

653

mirror (projection lens)

654

mirror (projection lens)

655

mirror (projection lens)

656

mirror (projection lens)

660

wafer table

661

coated substrate

700

DUV lithography system

701

DUV light source

702

DUV radiation/ray path

703

Beam Forming and Illumination System (DUV)

704

photomask

705

projection system

706

wafers

707

lens

708

mirror

709

optical axis

QUOTES INCLUDED IN DESCRIPTION

This list of the 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

• WO 2022023313 A1 [0008]

Claims (14)

Optical element (100) with a body (101) onto which at least one first conductor track (102) and a second conductor track (103) are applied or introduced, and with at least one electrical component (107), characterized in that the at least one electrical component (107) has a first electrical contact surface (105) and a second electrical contact surface (106) spaced apart from the first electrical contact surface (105), that the electrical component (107) with the electrical conductor tracks (102, 103) is electrically conductive by means an electrically conductive adhesive applied over a surface or in a structured manner is connected in such a way that the first electrical contact area (105) is electrically conductively connected to the first conductor track (102) and the second electrical contact area (106) is electrically conductively connected to the second conductor track (103), the first electrical contact surface (105) and the second electrical contact surface (106) are electrically insulated from one another. Optical element (100) according to claim 1 , characterized in that the electrically conductive adhesive is formed as an anisotropically electrically conductive adhesive. Optical element (100) according to claim 1 or 2 , characterized in that the electrically conductive adhesive is applied exclusively to the electrical contact surfaces (105, 106). Optical element (100) according to claim 3 , characterized in that an insulating surface (109) is formed between the first electrical contact surface (105) and the second electrical contact surface (106), and in that an electrically non-conductive adhesive is applied to the insulating surface (109). Optical element (100) according to claim 1 , characterized in that the structured application has at least a first segment (110) with a plurality of spaced-apart first adhesive points (111) of an electrically conductive adhesive and a second segment (112) with a plurality of spaced-apart second adhesive points (113) of an electrically conductive adhesive, and in that the first segment (110) and the second segment (112) are spaced from one another such that electrical connection between the electrical contact surfaces (105,106) is prevented. Optical element (100) according to claim 5 , characterized in that a first center distance (118) between first adhesive points (111) is smaller than the second center distance (119) between a first adhesive point (111) of the first segment (110) arranged at the edge and a first adhesive point (111) facing this second adhesive point (113) arranged at the edge of a second segment (112) adjacent to the first segment (110). Optical element (100) according to any one of Claims 1 until 6 , characterized in that the at least one electrical component (107) is formed as an actuator (104). Optical element (100) according to any one of Claims 1 until 7 , characterized in that the at least one electrical component (107) is formed as a sensor. Optical element (100) according to any one of Claims 1 until 8th , characterized in that the at least one electrical component (107) is designed as a temperature control element. Optical element (100) according to any one of Claims 1 until 9 that a plurality of different electrical components (107) is present. Optical element (100) according to any one of Claims 1 until 10 , characterized in that each electrical component (107) has at least one further electrical contact surface in addition to the first electrical contact surface and the second electrical contact surface. Optical element (100) according to any one of Claims 1 until 11 , characterized in that the first contact surface 105 and the second contact surface 106 are both arranged spaced apart from one another on one of the surfaces of the electrical component 107 facing the body 101 . Optical element (100) according to any one of Claims 1 until 12 , characterized in that the first contact surface (105) and the second contact surface (106) are arranged on different surfaces of the electrical component (107). Optical element (100) according to any one of Claims 1 until 13 , characterized in that the optical element (100) is formed as an adaptive mirror (200), and that the body (101) comprises a mirror substrate (115) or that the body (101) comprises a mirror substrate (115) and a backplate (116 ) comprises, wherein the at least one electrical component (107) with the mirror substrate (115) and/or the back plate (116).

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