WO2019016235A1

WO2019016235A1 - Optical system, lithography machine, method for producing an optical system, and method for replacing a module

Info

Publication number: WO2019016235A1
Application number: PCT/EP2018/069441
Authority: WO
Inventors: Joachim Hartjes; Toralf Gruner; Steffen FITZSCHE
Original assignee: Carl Zeiss Smt Gmbh
Priority date: 2017-07-21
Filing date: 2018-07-17
Publication date: 2019-01-24
Also published as: DE102017212534A1

Abstract

An optical system (200) for a lithography machine (100A, 100B), comprising a first module (202) designed to surround a first part of a beam path (214), a second module (204) which can be connected to the first module (202) and is designed to surround a second part of a beam path (214), and a sensor device (228) provided on the first module (202) and configured to detect a position of the second module (204) relative to the first module (202) independently of and/or outside the beam path (214), so as to align the first module (202) and the second module (204) with each other on the basis of measurements obtained by the sensor device (228), wherein the first module (202) and/or the second module (204) has a mirror (212, 222).

Description

OPTICAL SYSTEM, LITHOGRAPHIC SYSTEM, METHOD FOR PRODUCING AN OPTICAL SYSTEM AND METHOD FOR PROCESSING

REPLACING A MODULE The content of the German priority application DE 10 2017 212 534.9 (application ^¬ day: July 21, 2017) is hereby fully incorporated.

The present invention relates to an optical system for a Lithographiean ^¬ location. Furthermore, the present invention relates to a lithography system with such an optical system. Moreover, the present invention relates to various embodiments of a method for producing a derar ^¬ term optical system. In addition, the present invention relates to a method for exchanging a module of such an optical system for a litho ^¬ graphieanlage.

Microlithography is used to fabricate microstructured devices, such as integrated circuits. The microlithography phieprozess is performed with a lithography system, which has a loading ^¬ lighting system and a projection system. The image of an illuminated by the illumination system mask (reticle) is in this case projected by means of the Pro ^¬ jektionssystems was bonded to a photosensitive layer (photoresist) be ^¬-coated and which is arranged in the image plane of the projection system substrate (e.g. a silicon wafer) for the mask structure to transfer to the light ^¬ sensitive coating of the substrate.

Driven by the desire for ever smaller structures in the herstel ^¬ development of integrated circuits are currently escape EUV lithography tools ^¬ oped which light having a wavelength in the range of 0.1 to 30 nm (nanometer), in particular 13.5 nm, use. In such EUV lithography systems must because of the high absorption of light of this wavelength of most materials reflective optics, ie mirror, instead of - as before - bre ^¬ sponding optics, ie lenses are used. Projection objectives of a lithography system can have a modular structure. This is particularly advantageous when the projection lenses exceed a certain size. For example, modules of a projection lens can be brought to a location where the lithography system and only at a ^¬ be assembled or connected sentence location. The assembly derarti ^¬ ger modules has high accuracy requirements.

For example, the positions of two modules to be connected can be detected by means of a coordinate measuring machine (CMM). From the detected Po ^¬ sitions a positional relationship between the modules can be determined. The coordinate measuring machine references outer surfaces of the module when detecting the position of a module. This can limit the accessibility of the modules for assembly personnel. Therefore, a position of a module relative to another module based on the detected data only ^¬ SUC gene after the individual positions of the modules has been detected and determines the location ^¬ relationship. There are thus at least two Messiterationen he ^¬ conducive until a satisfactory positional relationship between the modules is set by the assembly personnel.

In addition, the modules are re ^¬ ferenziert each other with respect to an end stop. For modules for example have a mass greater than 100 kg or so ^¬ even more than 250 kg can therefore occur incorrect positions that exceed a required accuracy of eg 40 μηι. Such mispositioning can not be compensated, for example, due to limited actuator rank.

Furthermore, such coordinate measuring machines must be adapted to a size of the Mo ^¬ modules, so that if large modules large coordinate measuring machines have to be provided and appropriate manufacturing technology Gren ^¬ zen can be achieved. Furthermore, coordinate measuring machines are known which operate using inductive Sen ^¬ sors. Furthermore, coordinate measuring machines are known that example by a mechanical probing, so contact, measure at ^¬. As soon as a predetermined contact force of the probe is reached on the test object, the position is recorded as a data point. For example, so-called load cells are used to determine the contact pressure. The determination of the position of the probe of the coordinate measuring machine, for example, by means of sensors that use a structured glass scale, such as Git ^¬ tersensoren.

Against this background, it is an object of the present invention to provide an improved optical system, an improved lithography apparatus, a ver ^¬ improved method of manufacturing an optical system and a verbes ^¬ Sertes method for replacing a module.

Accordingly, an optical system for a lithography system provided schla ^¬ gene, having a first module which is adapted to enclose a first portion of a beam path, a (with the first module, in particular di ^¬ rectly ie without the interposition of further modules, components, floors Foundations or elements), a connectable second module configured to enclose a second part of the beam path, and a sensor device provided on the first module and configured to position the second module relative to the first module, for example, independently and / or except ^¬ half of the beam path, to detect, to align the first module and the second module based on each detected by the sensor device measurements. For example, the first module and / or the second module has a mirror.

By providing the sensor device on the first module, the position of the second module relative to the first module can be detected directly. This makes it possible to measure from the inside of the modules, so that, for example, an inner surface or an inner region of the second module for the sensor device can be used as measurement serves as a reference. Furthermore, there is the advantage that an alignment of the first module can be performed relative to the second Mo ^¬ dul same time as the He ^¬ take a position as eg not einge- accessibility of the two modules for assembly ^¬ personnel by a measuring procedure by means of the sensor means is restricted.

The term "optical path" of the geometrical course of light rays (working ^¬ light) is ver ^¬ stood towards a target object such as a wafer to be exposed. By "work light" is in the present light or a light beam are to be comparable, which for exposure in the optical system is used to transmit a Mas ^¬ kenstruktur on a photosensitive coating of the substrate (in particular microstructured component). Means "Regardless of the Strah ^¬ beam path" means that no working light for the detection using the Sensorein ^¬ direction is used and / or that not measured by an operating light path. "Outside of the beam path" means that there is spatially a ^distance between the beam path and the sensor device. Preference ^¬ as the sensing with the aid of the sensor device is independent of jegli ^¬ chen optical elements which are adapted to form the geometric profile of the beam path.

For example, "position" means an orientation and / or position of the second module relative to the first module or vice versa. An orientation means at ^¬ game as a positional relationship described by at least one rotational degree of free ^¬ standardized, in particular three rotational degrees of freedom. A position means, for example, a positional relationship that is described by at least one translational degree of freedom, in particular three translational degrees of freedom. The "detection" of a layer can, for example, also be referred to as measuring. "Enclosing the beam path" means that the beam path passes through the first and second modules. Preferably, the first module comprises a first Mo ^¬ dulgehäuse, in particular a first vacuum enclosure, and the second module second module housing, in particular a second vacuum housing, wherein the ers ^¬ te module housing is flanged to the second module housing or vice versa. The first and second vacuum housings are adapted to maintain a (high) vacuum (as required for the use of EUV light) in their interior in an interconnected state. Preferably, the sensor device is arranged inside or outside the first vacuum housing and / or the second vacuum housing and / or the vacuum. The module housing are formed for example of a solid material. In this case, the first module housing can be connected to the second module housing such that an alignment with one another is adjustable. Preferably, tung a Einstellvorrich-, in particular a printing mechanism, seen at at least one of the modules before ^¬ order relative to the second module or vice versa, to adjust a position of the first module. The pressure mechanism may include adjustment screws and / or micrometer screws. In other words, a SET ^¬ development of the modules to each other, ie, the change in position from each other, for example, by shifting one of the two modules on a common interface ^¬ position resp interface surface enforceable. Introducing an adjustment force required for this can be done with a tool or with ^¬ means of the printing mechanism, for example by means of knocking. For example, this process can take place at a certain weight ^¬ relief, so that the adjustment force is reduced for a reduction of friction or frictional forces.

The first and second modules are particularly adapted to be connected to each other. Preferably, the second module is only rigidly connectable to the first module, so that in particular no actuated movements between the entire first module relative to the entire second module are possible.

For example, the first and / or the second module comprises at least one optical element, in particular a lens or a mirror, which at least partially defines or geometrically shapes the beam path. Furthermore, a module may comprise actuators for, in particular, each optical element which optimizes are assigned element and are adapted to set or change a position of the optical element. The actuators can also be called Akto ^¬ ren or actuators. It is understood that a module may also comprise more than one optical element, eg two, three, four or five optical elements. Preferably, the first and / or second module comprises a light inlet opening, which is provided for an entry of the working light into the module, and a light exit opening, which is provided for a discharge of the working light from the Mo ^¬ module. The sensor device may for example have one or more probes or be designed as a probe.

According to one embodiment, the first module encloses a first Innenvo ^¬ lumen and the second module a second internal volume, said first interior volume and the second internal volume is connected to a total interior volume in the connected state of the first module with the second module, and wherein said sensor means within the total internal volume is arranged.

The provision of the sensor device within the modules has the advantage that the detection of the position of the second module can take place in an interior of the modules and thus a smaller space requirement for the detection is necessary. For example, the second module an internal surface or for indoor comprises ^¬ rich serving as a measurement reference for the sensor device. Preferably, in the connected state of the modules facing a light entrance opening of the second module of a light exit opening of the first module, so that the work light can pass without obstacle from the first module into the second module.

According to a further embodiment, the first module and / or the second module has a weight of greater than 100 kg or greater than 250 kg.

May herein also be referred to as a mass "weight". Such di ^¬ directly will often detecting the position of the second module to the first module is relatively to large and correspondingly heavy modules particularly advantageous, since not necessarily ^¬ must be measured from the outside. Thereby, a measuring arrangement can be provided which is inexpensive. Preferably, the first module and / or the second module has a weight of 100 kg to 250 kg or 250 kg to 500 kg.

According to a further embodiment, the sensor device comprises a capacitive sensor and / or an inductive sensor and / or a confocal sensor and / or a triangulation sensor and / or a position-sensitive sensor and / or an encoder and / or an interferometer.

A capacitive sensor has the advantage that distance measurements can be measured with nanometer accuracy. The sensor device may comprise a plurality of sensors. Preferably, the sensor device comprises a distance sensor, a displacement sensor and / or an angle sensor. The Enco ^¬ is, for example, an optical encoder. Alternatively or additionally, the sensor device may comprise an optical sensor. It is understood that a plurality of capacitive, inductive or optical sensors may be provided. For example, the sensor device comprises only capacitive, inductive or optical sensors. The interferometer is in particular a miniature interferometer.

According to a further embodiment, the sensor device comprises a measuring bridge circuit, in particular a capacitance measuring bridge or inductance measuring bridge.

Such measuring bridge circuits are characterized by a high sensitive ^¬ ness. In addition, only moderate demands are placed on the precision of the individual elements. For example, the measuring bridge circuit is designed as a Wien bridge or Wien-Maxwell bridge. According to a further embodiment, the optical system comprises a struc ^¬ Rdevice to which the sensor device is mounted, wherein the struc ^¬ Rdevice is connectable to the first module and removable from vorgese ^¬ hen.

The structure element is, for example, a measuring gauge, which can be connected to the first Mo ^¬ dul to detect the position of the second module relative to the ers ^¬ th module. In this case, the sensor device is connected indirectly or indirectly to the first module. This has the advantage that the structural can be removed from the first module turelement including sensor means after one another orientation of the ers ^¬ th module to the second module, so that an alternative use for other modules is possible. Preference ^¬ wise, the structural element is aligned relative to the first module or jus ^¬ tierbar.

Alternatively, the sensor device can be connected to an Ab ^¬ section of the first module housing directly or directly.

According to a further embodiment, the structural element extends in a state connected to the first module through the first internal volume.

For example, the structural element of the to be connected or adapted to be connected to the inside of the first module housing ^¬ first Modulge ^¬ häuses with an inner side. This has the advantage that essentially no space has to be provided for the structural element outside the module housing.

Further, a projection lens for a lithography system with an optical system as described above, proposed, wherein the projection objective has a modular structure particularly for transportability and / or Manageable ^¬ ness. In addition, a lithography system is proposed as described before ^¬ standing with an optical system.

The lithography system may in particular be an EUV lithography system. EUV stands for "extreme ultraviolet" (English: extreme ultra violet, EUV) and refers to a wavelength of working light between 0.1 and 30 nm. DUV stands for "deep ultraviolet" (English: deep ultra violet, DUV) and denotes a wavelength of the working light between 30 and 250 nm.

In addition, a method for producing an optical system, in particular as described above, for a lithography system is proposed, comprising the steps of: a) providing a first module which is designed to enclose a first part of a beam path, b) providing one with the first module connectable second module, which is designed to enclose a two ^¬ th part of the beam path, wherein, for example, the first module and / or the second module has a mirror, c) providing a provided on the first module sensor device, d) connect the first module with the second module, e) detecting a position of the second module relative to the first module by means of the sensor device, wherein the detection example ^¬ independent and / or outside of the beam path, and f) to ^¬ each other aligning the first Module and the second module based on the detected in step e) location. According to a further embodiment, the sensor device is provided with a

Structural element connected, which is temporarily connected to the first module.

According to a further embodiment, the structural element together with the sensor device is removed from the first module after completion of step f). This has the advantage that unnecessary elements, such as the structural element, are removed for the lithography process.

According to another embodiment, step e) and step f) are carried out simultaneously.

This has the advantage that the assembly personnel, for example, while making the alignment of the modules to each other, the data on the detected position are available. This allows an alignment to be carried out in a time-efficient manner. Preferably, the optical system comprises an interface, in particular ^¬ a display that outputs the data to the detected position in real time or displays.

For example, the first module and the second module before the steps e) and f) by means of a coordinate measuring ^machine , in particular individually ver ^¬ measure. In particular, based on the measurement values of the coordinate measuring machine ^¬ a desired change in position of the first module can be determined at the second module. For example, the Strukturele ^¬ element is connected to the first module from time to time for step c). In a further step, a probe of the sensor device is set to "zero" and / or a first measuring reference is determined by means of the probe and in particular so that executed step e). In particular, in a further step, the desired La ^¬ geänderung of the first module to the second module or vice versa in Diffe ^¬ limits of probe measured values converted.

Preferably, step f) is subsequently executed, in particular iteratively, until the converted difference is determined, measured and / or displayed with the aid of the measuring probe, so that it can in particular be concluded that the desired change in position has been set. By way of example, the modules are subsequently fixed to one another or firmly connected to one another, for example by screwing. Preferably, step e) is then carried out again in order to control the position of the modules relative to one another. Furthermore, for example, in a downstream step, the structural element of the first module to be disconnected or disassembled. Such a method is particularly advantageous for Modulanordnun ^¬ gen that can not be measured by a coordinate measuring machine because of their overall size. Preferably, three, four, five or more modules can also be assembled using this method.

According to a further embodiment, step e) and step f) are repeated until a deviation of an actual position from a desired position of the second module relative to the first module in at least one spatial direction, in particular in each of two spatial directions ( each extending perpendicular zueinan ^¬ ) or in each of three spatial directions (each perpendicular to ^¬ each other), between 0 and 40 μηι, preferably between 0 and 38 μηι, more preferably between 0 and 36 μηι, more preferably between 0 and 34 μηι, more preferably between 0 and 32 μηι, more preferably between 0 and 30 μηι, more preferably between 0 and 20 μηι, more preferably between 0 and 10 μηι amounts.

"Actual position" as used herein means a position which is detected by means of the sensor device. "Desired position" means a position which is present in an ideal case, eg a calculated or predetermined position for which the modules are designed or which Li ^¬ thographieanlage is designed.

This has the advantage that incorrect positioning (deviation of the actual position from the desired position) of the modules relative to each other is so small that actuator ranges, of actuators which are set up to adjust a position of an optical element of the modules, suffice. to compensate for the incorrect positioning and the desired function of the modules or the lithography tool to ge ^¬ währleisten. It is understood that the method can also be applied when the first or second module is already connected to another module, which is to be formed as ^¬ to surround a further part of the beam path. Further, a method for exchanging a module of an optical Sys ^¬ tems, especially as described above, beaten for a lithographic system before ^¬, comprising the steps of: a) providing an optical system with egg nem first module that is adapted to a first To enclose part of a beam ^path , and a second module connected to the first module, which is designed to close a second part of the beam ^path , b) providing a structural element and a sensor device connected thereto, c) connecting the structural element the first module, d) detecting a position of the second module relative to the first module by means of the sensor device, e) separating the first module from the second module, f) be ^¬ riding provide a replacement module for replacing the first module and connecting the structural member with the Replacement module, g) connecting the replacement module to the second module, h) aligning the Ersatzmod and the second module based on the detected in step d) location.

With the aid of such a method it is possible to time-efficient and zutauschen with high precision, for example, a damaged or in need of maintenance module ^¬.

According to one embodiment, the step h) while running or wi ^¬ derholt until a deviation of an actual location of a target position of the second Mo ^¬ duls relative to the replacement module in at least one spatial direction, insbesonde ^¬ re in each of two directions in space (which each run perpendicular to each other) or in each of three spatial directions (each perpendicular to each other), between 0 and 40 μηι, preferably between 0 and 38 μηι further ^¬ preferably between 0 and 36 μηι, more preferably between 0 and 34 μηι, more preferably between 0 and 32 μηι, more preferably between 0 and 30 μηι, more preferably between 0 and 20 μηι, more preferably between 0 and 10 μηι, be. In step e), for example, the same structural element that is removed from the first module after step d) can be used for the replacement module. Alternatively, another, in particular structurally identical, structural element for step f) can be provided.

In addition, a method of manufacturing an optical system, insbeson ^¬ particular as described above, proposed for a lithography system, comprising the steps: enclosing a) providing a first module that is adapted to ei ^¬ NEN first part of an optical path, b) to enclose providing a connectable to the first module the second module, which is adapted to a second part of the beam path, c) providing a kapaziti ^¬ ven sensor, d) connecting the first module to the second module, e) detecting a position of the first Module and a position of the second module by means of the ka ^¬ pazitiven sensor, and f) each other aligning the first module and the second module based on the detected in step e) layers.

By be determined by means of a capacitive sensor, the positions of the first and second Mo ^¬ duls, a high accuracy of measurement can be achieved. Distance measurements can be measured, for example, with nanometer accuracy. Furthermore, a plurality of capacitive sensors can be provided. Before ^¬ preferably the sensor as the distance sensor, distance sensor or angle sensor is formed from ^¬. Furthermore, capacitive distance sensors and Win ^¬ kelsensoren example, are provided. Further, for example, the positions are determined with the aid of a capaci ^¬ tätsmessbrücke.

According to one embodiment, the capacitive sensor is provided on a coordinate measuring machine, which is arranged for detecting the layers in step e) next to the first and / or second module. This has the advantage that a measurement of an outside of the modules can be passed through ^¬. Alternatively or additionally, a measurement with help a structural element, on which the capacitive sensor is arranged, are performed from the inside.

According to a further embodiment, step e) and step f) are repeated until a deviation of an actual position from a desired position of the second module relative to the first module in at least one spatial direction, in particular in each of two spatial directions ( each extending perpendicular zueinan ^¬ ) or in each of three spatial directions (each perpendicular to ^¬ each other), between 0 and 40 μηι, preferably between 0 and 38 μηι, more preferably between 0 and 36 μηι, more preferably between 0 and 34 μηι, more preferably between 0 and 32 μηι, more preferably between 0 and 30 μηι, more preferably between 0 and 20 μηι, more preferably between 0 and 10 μηι amounts. The embodiments and features described for the proposed optical system apply correspondingly to the proposed method and ^vice versa. The beschrie ^¬ surrounded for the method for manufacturing the optical system embodiments and features apply to the proposed procedural ^¬ ren for replacing the module of the optical system corresponding to and vice versa. The embodiments and ^features described for the first module apply correspondingly to the second module and vice versa.

In the present case, "a" is not necessarily to be understood as restricting to exactly one element. Rather, several elements, such as two, three or more, may be provided. Also, any other count word used herein is not to be understood as having an accurate restriction to just the corresponding number of elements. Rather tenacious ^¬ lenmäßige deviations above and below are possible. Other possible implementations of the invention include non-expli ^¬ zit Combinations of above or below with respect to the exporting approximately ^¬ Examples features or embodiments described. It will the skilled person also add individual aspects as improvements or additions to the respective basic form of the invention.

Further advantageous embodiments and aspects of the invention are the subject of the dependent claims as well as the execution ^¬ embodiments of the invention described below. Furthermore, the invention by way of Favor ^¬ th embodiments with reference will be explained in more detail to the accompanying figures. Fig. 1A shows a view of an EUV lithography system; Fig. 1B is a view of a DUV lithography apparatus;

FIG. 2 shows a schematic sectional view of an embodiment of an optical system for the lithography system according to FIG. 1A or 1B; FIG.

FIG. 3 shows a schematic sectional view of a further embodiment of an optical system for the lithography system according to FIG. 1A or 1B; FIG. 4 shows a schematic sectional view of a further embodiment of an optical system for the lithography system according to FIG. 1A or 1B;

5 shows a schematic sectional view of a further embodiment of an optical system for the lithography system according to FIG. 1A or 1B;

Fig. 6 shows a block diagram of a method of manufacturing the optical system according to one of Figs. 2, 3 or 5;

Fig. 7 is a block diagram of a method of replacing a module of the optical system according to any one of Figs. 2-5; and FIG. 8 shows a block diagram of a method for manufacturing the optical system according to FIG. 4 or 5.

In the figures, identical or like elements with the same function have been provided Be ^_ reference symbols, unless otherwise indicated. As far as a reference number has several reference lines in the present case, this means that the corresponding element is present multiple times. It should also observe the ^¬ that the representations ^¬ are quite in the figures are not necessarily dimensioning true to scale.

Fig. 1A is a schematic view of an EUV lithography apparatus 100A, which includes a beam shaping and illumination system 102 and a projection system 104 ^¬. Here, EUV stands for "extreme ultraviolet" (English: ext ^¬ reme ultraviolet, EUV). And denotes a wavelength of the working light be- see 0.1 and 30 nm, the radiation and illumination system 102 and the Pro ^¬ jektionssystem 104 are each in seen a vacuum housing, not shown before ^¬, wherein the vacuum housing is evacuated by means of a not shown Evakuie ^¬ reasoning apparatus. the vacuum housing are surrounded by a non-illustrated machine room is provided in which driving devices for the mechanical procedure and adjusting the optical elements Furthermore, electrical controls and the like may also be provided in this machine room.

The EUV lithography system 100A has an EUV light source 106A. As EUV light source 106A, for example, a plasma source (or synchrotron) may be provided, which radiation 108A in the EUV range (extreme ultraviolet range), ie z. B. in the wavelength range of 5 to 20 nm emitted. In radiation and illumination system 102, the EUV radiation is 108A gebün ^¬ delt filtered and the desired operating wavelength of the EUV radiation 108A manufacturer. The EUV radiation 108A produced by the EUV light source 106A has a relatively low transmissivity by air, which is why the beam radiation management rooms in the radiation and illumination system 102 and in Projekti ^¬ onssystem 104 are evacuated.

The radiation and illumination system 102 illustrated in FIG. 1A has five mirrors 110, 112, 114, 116, 118. After the passage through the radiation ^¬ and illumination system 102, the EUV radiation 108A is on a photomask (English: reticle) directed 120th The photomask 120 is also formed as a reflective op ^¬ table element and may be provided outside of the systems 102, 104 may be angeord ^¬ net. Further, the EUV radiation 108A may be directed to the photomask 120 by means of a mirror 122. The photomask 120 has a structure wel ^¬ surface by means of the projection system 104 reduces to a wafer 124 or the like is imaged.

The projection system 104 (also referred to as a projection objective) has six mirrors M1 to M6 for imaging the photomask 120 onto the wafer 124. Since ^¬ mirror Ml be arranged to M6 of the projection system 104 symmetrically with respect to an optical axis 126 of projection system 104 in a single can. It should be noted that the number of mirrors of the EUV lithography system 100A is not limited to the number shown. It can also be provided more or less mirror. For example, the projection system 104 may include ten mirrors. Furthermore, the levels are usually at their pre ^¬ the side curved for beam shaping. In another embodiment, the projection system 104 may be embodied without an optical axis, wherein one or more mirrors M1 to M6 are designed as free-form surfaces.

Fig. 1B is a schematic view of the DUV lithography system 100B, che wel ^¬ a beam shaping and illumination system 102 and a projection system 104 includes. DUV stands for "deep ultraviolet" (English: deep ultra violet, DUV) and denotes a working light wavelength between 30 and 250 nm. The DUV lithography system 100B has a DUV light source 106B. As a DUV light source 106B, for example, an ArF excimer laser can be provided, which radiation 108B in the DUV range, for example, 193 nm emit ^¬ advantage.

The Strahlungsformungs- and illumination system 102 shown in Fig. 1B forwards the DUV radiation 108B on a photomask 120. The photomask 120 is formed as a transmissive optical element, and may be outside the Syste ^¬ me 102, 104 disposed to be. The photomask 120 has a structure which is reduced by means of the projection system 104 onto a wafer 124 or the same ^¬ is imaged.

The projection system 104 has a plurality of lenses 128 and / or mirrors 130 for imaging the photomask 120 onto the wafer 124. In this case, individual lenses 128 and / or mirrors 130 of the projection system 104 may be arranged symmetrically to egg ^¬ ner optical axis 126 of the projection system 104. It should be noted that the number of lenses and mirrors of the DUV system 100B is not limited to the number shown. It is also possible to provide more or ^fewer lenses and / or mirrors. Furthermore, the mirrors are usually curved at their front for beam shaping.

An air gap between the last lens 128 and the wafer 124 may be replaced by a liquid medium 132, which has a refractive index greater than 1 on ^¬ . The liquid medium may be, for example, high purity water. A sol rather structure is referred to as immersion lithography and has he ^¬ creased photolithographic resolution on.

2 shows a schematic sectional view of an optical system 200 for the lithography system 100A, 100B. The optical system comprises a module 202 and a module 204. For example, the module 202 may be referred to as a first module and the module 204 may be referred to as a second module. The module 202 comprises a module housing 206 (in particular a vacuum housing) which has an outer wall Formation of the module 202 forms. The module housing 206 has a light entry opening ^¬ 208, may be incident through the work light 210 in the module housing 206th The module housing 206 encloses an internal volume 230, through which the working light 210 can propagate. Further, the module housing 206 includes a light exit opening 209 through which the light is incident work 210 and the Mo ^¬ dul 202 leaves. The module 202 may be connected to the light entrance opening 208 with another module (not shown in FIG. 2).

In the module 202. Furthermore, an optical element 212, in particular a mirror, is provided, on which the light falls work 210 and reflectors ^¬ advantage of this example. The working light 210 follows a course in the optical system and thereby forms a beam path 214. In this case, the module 202 is designed to ^¬ to enclose a first part of a beam path 214 by means of the module housing 206. Furthermore, the module housing 206 includes a light exit opening, through which the working light 210 leaves the module 202 and drops directly into the module 204. The optical element 212 is, for example, one of the Spie ^¬ gel Ml - M6, the mirror 110, 112, 114, 116, 118 (see Fig. 1A) or one of the Lin ^¬ sen 128 (see Fig. 1B). The module 204 includes a module housing 216 (specifically, a Vakuumgehäu ^¬ se) forming an outer wall of the module 204th The module housing 216 has a light entry port 218, may be incident in the Mo ^¬ dulgehäuse 216 by the work light 210th The module housing 216 encloses a Innenvo ^¬ lumen 232, through which the working light 210 can propagate. Furthermore, the module 204 comprises a light exit opening 220, through which the working light 210 falls and leaves the module 204. The module 204 may be connected to the light exit opening ^¬ 220 with another module (in Fig. 2 not shown). Furthermore, an optical element 222, in particular a mirror, is provided in the module 204, onto which the working light 210 falls and is reflected by it eg in the direction of the light exit opening 220. In this case, the module 204 is designed to enclose a second part of the beam path 214 by means of the module ^¬ housing 216. The optical element 222 is, for example, one of the gel M1-M6, the mirror 110, 112, 114, 116, 118 (see FIG. 1A) or one of the ^lenses 128 (see FIG. 1B). The module 202 and / or module 204 have a Ge ^¬ weight of greater than 100 kg, greater than 250 kg. The module 202 is connectable to the module 204, and Darge ^¬ presented case with the module 204 is connected in the in Fig. 2 at a joining point 224th The module may be attached ^¬ flanged to the module 204 by means of connecting means 226,202. For example, one of the connecting means 226 comprises screws ^¬ ben. The screws can be screwed for example by the module 202, in particular a transit hole of the module 202, and inserted into a thread (not shown) of Mo ^¬ duls 204th

Alternatively or additionally, the screws 204 can both modules 202, 204, in particular through-holes (not shown) of the two modules 202, Ge inserted and by means of nuts (not shown) are fixed, so that a Verbin ^¬ dung power between the modules 202, 204 prevails. Alternatively or zusätz ^¬ Lich, the modules 202, 204 include edges which are pressed together by a Klemmme ^¬ mechanism (not shown). Such Klemmme ^¬ mechanism is, for example by means of screws, in particular adjusting screws, betätig- bar.

In the connected state of the module 202 to the module 204, the Innenvo ^¬ lumen 230 and the internal volume 232 to be a total internal volume of 234 ver ^¬ prevented. In this case, the light exit opening 209 faces the light entry opening 218, the light exit opening 209 and the light entry opening 218 at least partially overlapping, so that the work light 210 falls from the module 202 into the module 204.

In the operation of the optical system 200 prevails in the event that the working light 210 is EUV light, a high vacuum in the total internal volume 234. The Mo ^¬ dulgehäuse 206, 216 may be formed correspondingly sealing. Further, the optical system 200 includes a sensor device 228 which is adapted to independently and / or outside of the beam path 214 to detect a position of the module 204 to the module 202, insbesonde ^¬ re relatively. It can further be provided that the sensor device ^{(~ 6} mbar, for example. Pressure <10) is located within 228 or au ^¬ ßerhalb the high vacuum. In the exemplary embodiment shown here, the sensor device 228 is arranged within the high vacuum. Similarly, the sensor device 228 could be located outside the high vacuum, as shown for the embodiment of FIG.

The sensor device 228 is arranged within the total internal ^volume 234. When the two modules 202, 204 are joined, the module 202 is aligned with the module 204 based on measured values acquired by the sensor device 228. The module housing 216 comprises an inner surface 236 or an inner region which is configured to be referenced by the sensor device 228 to capture the location of the module 204. It goes without saying that a plurality of inner surfaces or inner regions can also be set up to be referenced by the sensor device 228.

The sensor device 228 includes, for example, a capacitive or inductive Sen ^¬ sor. The sensor device 228 may be a measuring bridge circuit, and in particular ^¬ sondere comprise a capacitance measuring bridge or Induktivitätsmessbrücke. In Fig. 2 is in the modules 202, 204 each have an optical element 212, 222 ge ^¬ shows. It is understood that in each of the modules 202, 204, two, three or more optical elements may be provided. For example, no optical element can be provided in one or both modules 212, 222. Fig. 3 shows in a schematic sectional view of a further embodiment of an optical system 200. In contrast to FIG. 2, 200 includes the optical Sys tem ^¬ a structural element 300, to which the sensor device 228 befes- is done. The structural element 300 is connected to the module 202 and can be removed therefrom without destruction. In this case, the struc ^¬ Rdevice 300 extends over an entire length L of the internal volume 230, wherein the structural element 300 for fastening to an outer side 302 of the Modulgehäu- ses can project ^¬ from the internal volume 230 through the light entry port 208 out 206th For example, a fixing means 304 for fixing the structural member 300 to the outside 302 is provided. Furthermore, the structural element 300 protrudes in into the interior volume 232, the Sensoreinrich ^¬ processing is provided in the internal volume 232 228th

Preferably, an adjustment device 306, in particular a Druckmecha ^¬ mechanism provided on the module 202, the module 204 and / or in a Schnittstellenbe ^¬ rich 308 between the module 202 and the module 204 to the position of the module 202 relative to the module 204 or vice versa.

Fig. 4 shows another embodiment of an optical system 200. In the Un ^¬ terschied to FIG. 3, the optical system 200 comprises any sensor device 228, and no structural element 300, which are ^¬ arranged within the total internal volume of 234.

The optical system 200 includes a capacitive sensor 400, which is provided at a Ko ^¬ ordinatenmessmaschme 402 and is adapted to detect a position of the module 202 and a position of the second module 204 relative to the coor ^¬ dinatenmessmaschme 402nd Based on the detected by the capacitive sensor 400 layers, the module 202 relative to the module 204 from ^¬ richtbar.

The coordinate measuring machine 402 is arranged next to the module 202 and / or the module 204. In this case, the capacitive sensor 400 references an outer surface 404 of the module housing 206, which faces the capacitive sensor 400. Furthermore, the capacitive sensor 400 references an outer surface 406 of the module housing 204, which faces the capacitive sensor 400. It is understood that may be a plurality of capacitive sensors 400 provided to grasp the position of the module 202 and the location of the second module 204 to he ^¬. Furthermore, other types of sensors may be provided. The coordinate measuring machine 402 may be additionally used also in the embodiment shown in Fig. 2 exporting ^¬ approximate shape to detect additional data.

Fig. 5 shows a schematic sectional view of another embodiment of an optical system 200. In this case, Figure 5 shows, a development of Fig. 3. In addition to the embodiment shown in FIG. 3, 200, the optical Sys ^¬ tem shown in Fig. 5 coordinate measuring machine 402. At the coordina ^¬ tenmessmaschine 402 is provided a sensor device 228 and / or a capacitive sensor 400 that references the outer surfaces 404, 406th A derarti ^¬ ge arrangement has the advantage that both from the outside, the position of the module 202 and the module 204 relative to the coordinate measuring machine 402 and from the inside a position of the module 204 relative to the module 202 can be detected.

For example, the detection of the position by means of the sensor device 228 from the inside in real-time or online, and the detection of the documents by means of co ordinatenmessmaschine 404 is carried out iteratively after a completed alignment ^¬ step of module 202 relative to the module 204 by the assembly personnel.

6 shows a block diagram of a method for producing the optical system 200 for the lithography system 100A, 100B according to one of FIGS. 2, 3 or 5. In a step S1, the module 202 is provided. In a step S2, the connectable to the module 202 module 204 is provided wherein at ^¬ game as the module 202 and / or the module 204, a mirror 212, 222 has ^¬. In a step S3, the sensor 202 provided on the module 202 ^¬ device 228 is provided. In a step S4, the module 202 is connected to the module 204. In a further step S5, a position of the module 204 relative to the module 202 is detected by means of the sensor device 228, wherein the detection in particular independently and / or outside of the beam path 214 takes place. In addition, in a step S6, the module 202 and the module 202 are aligned with each other based on the position detected in the step S5.

The structural element 300, together with the sensor device 228, is removed from the module 202 after the end of step S6. Preferably, step S5 and step S6 are executed simultaneously.

7 shows a block diagram of a method for exchanging a module of the optical system 200 according to one of FIGS. 2-5

Step S02, the optical system 200 is provided with the module 202 and the module 204 connected to the module 204.

In a step S20, the structural element 300 and the sensor device 228 connected thereto are provided. In a step S30, the structure element 300 is connected to the module 202. Further, in a step S40, a position of the module 204 is detected relative to the module 202 by means of the Sensorein ^¬ direction 228th In a step S50, the module 202 is disconnected from the module 204. In a step S60, a replacement module for replacing the Mo ^¬ duls 202 and connecting the structural element 300 with the replacement module is provided readiness. In a step S70, the replacement module with the module 204 verbun ^¬. In addition, in a step S80, the replacement module and the module 204 are aligned with each other based on the position detected in step S40.

FIG. 8 shows a block diagram of a method for manufacturing the optical system 200 according to FIG. 4 or 5. In this case, the module 202 is provided in a step S100.

Furthermore, the module 204 which can be connected to the module 202 is provided in a step S200. In step S300, the capacitive sensor 400 is provided. In a step S400, the module 202 to the module 204 is verbun ^¬. In a step S500, the position of the module 202 and the position of the Mo ^¬ duls 204 by means of the capacitive sensor 400 is detected. Continue to be in one Step S600, the module 202 and the module 204 aligned based on the detected in step S500 layers.

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

LIST OF REFERENCE NUMBERS

100A EUV lithography system

100B DUV lithography system

102 radiation and lighting system

104 projection system, projection lens

106a EUV light source

106b DUV light source

108a EUV radiation

108b DUV radiation

110 - 118 mirrors

120 photomask, reticle

122 mirrors, grazing incidence mirrors

124 wafers

126 optical axis

128 lens

130 mirrors

132 immersion liquid

200 optical system

202 module

204 module

206 module housing

208 light entry opening

209 light exit opening

210 work light

212 optical element

214 beam path

216 module housing

218 light entry opening

220 light exit opening

222 optical element

224 joint 226 connecting means

228 sensor device

230 internal volume

232 internal volume

234 total internal volume

236 inner surface

300 structural element

302 outside

304 fastener 306 adjustment device

308 interface area

400 sensor

402 coordinate measuring machine

404 outer surface

406 outer surface

L length

Ml - M6 mirror

Sl step

S2 step

53 step

54 step

55 step

56 step

S10 step

S20 step

S30 step

S40 step

S50 step

S60 step

S70 step

S80 step S100 Step S200 Step S300 Step S400 Step S500 Step S600 Step

Claims

1. Optical system (200) for a lithography system (100A, 100B), with

a first module (202) adapted to enclose a first part of a beam path (214),

to enclose a with the first module (202) connectable to the second module (204) which is formed as ^¬ to a second portion of the beam path (214), and

take a on the first module (202) provided sensor means (228) which is adapted to a position of the second module (204) relative to the first module (202), independently and / or outside of the beam path (214) to he ^¬ for aligning the first module (202) and the second module (204) to one another based on measured values acquired by the sensor device (228), wherein the first module (202) and / or the second module (204) comprises a mirror (212, 222 ) having.

The optical system of claim 1, wherein the first module (202) encloses a first interior volume (230) and the second module (204) encloses a second interior volume (232), wherein when the first module (202) is connected to the second module (204) are connected to the first internal volume (230) and the second inner volume (232) to a total internal volume (234) and said Sen ^¬ soreinrichtung (228) is disposed within the total internal volume (234).

3. An optical system according to claim 1 or 2, wherein the first module (202) and / or the second module (204) has a weight of greater than 100 kg or greater 250 kg.

4. Optical system according to one of claims 1 - 3, wherein the Sensoreinrich ^¬ device (228) comprises a capacitive or inductive sensor and / or an encoder.

5. Optical system according to one of claims 1 - 4, wherein the Sensoreinrich ^¬ device (228) comprises a measuring bridge circuit, in particular a capacitance measuring bridge or inductance measuring bridge.

6. An optical system according to any one of claims 1-5, further comprising a structural element (300) to which the sensor device (228) is attached, where ^¬ in the structural element (300) with the first module (202) connectable and removable from this is provided.

7. An optical system according to claim 2 and 6, wherein the structural element (300) in connected to the first module (202) state by the first In ^¬ nenvolumen (230).

8. lithography system (100A, 100B) with an optical system (200) according to one of claims 1-7.

9. A method of manufacturing an optical system (200) for a Lithography ^¬ phieanlage (100A, 100B), comprising the steps of:

a) providing (S1) a first module (202) which is designed to enclose a first part of a beam path (214),

b) providing (S2) a second module (204) which can be connected to the first module (202) and which is designed to enclose a second part of the beam path (214), wherein the first module (202) and / or the second module (204) has a mirror (212, 222),

c) providing (S3) a (on the first module 202) provided Sensorein ^¬ direction (228)

d) connecting (S4) the first module (202) to the second module (204), e) detecting (S5) a position of the second module (204) relative to the first module (202) by means of the sensor device (228) the detection (S5) takes place independently of and / or outside the beam path (214), and

f) aligning (S6) the first module (202) and the second module (204) based on the position detected in step e).

10. The method of claim 9, wherein the sensor device (228) having a structural element (300) which is connected ^¬ time as with the first module (202) is connected.

11. The method of claim 10, wherein the structural element (300) together with Sen ^¬ soreinrichtung (228) after completion of step f) of the first module (202) is removed.

12. The method according to any one of claims 9 - 11, wherein the step e) and the step f) are carried out simultaneously.

13. The method of claim 9, wherein the step e) and the step f) are repeated until a deviation of an actual position from a desired position of the second module (204) relative to the first module (202) in at least one spatial direction between 0 and 40 μηι, preferably between 0 and 38 μηι, more preferably between 0 and 36 μηι, more preferably 0 and 34 μηι, 0 and 32 μηι, more preferably 0 and 30 μηι, more preferably 0 and 20 μηι, more preferably 0 and 10 μηι, is.

14. A method of replacing a module (202) of an optical system (200) for a lithography system (100A, 100B), comprising the steps of:

a) providing (S10) for enclosing an optical system (200) having a first module (202) is adapted to a first portion of a beam path (214), and one (with the first module 202) Associated second Mo ^¬ duls (204) adapted to enclose a second part of the beam path (214),

b) providing (S20) of a structural element (300) and a ^¬ NEN sensor means so that laminates (228)

c) connecting (S30) the structural element (300) to the first module (202), d) detecting (S40) a position of the second module (204) relative to the first module (202) by means of the sensor device (228), e) disconnecting (S50) the first module (202) from the second module (204), f) providing (S60) a replacement module for replacing the first module (202) and connecting the structural element (300) to the replacement module,

g) connecting (S70) the replacement module to the second module (204),

h) aligning (S80) the replacement module and the second module (204) based on the position detected in step d).

15. A method for manufacturing an optical system (200) for a Lithography ^¬ phieanlage (100A, 100B), comprising the steps of:

a) providing (S100) to enclose a first module (202) which is adapted ei ^¬ NEN first part of a beam path (214)

b) providing (S200) a second module (204) which can be connected to the first module (202) and which is designed to enclose a second part of the beam path (214),

c) providing (S300) a capacitive sensor (400),

d) connecting (S400) the first module (202) to the second module (204), e) detecting (S500) a position of the first module (202) and a position of the second module (204) by means of the capacitive sensor (400) , and

f) aligning with each other (S600) of the first module (202) and the second Mo ^¬ duls (204) based on the detected in step e), layers.

16. The method of claim 15, wherein the capacitive sensor (400) is provided on a coordinate measuring machine (402) arranged adjacent to the first and / or second module (202, 204) for detecting the layers in step e).