The contents of German patent application DE 10 201 1 086 949.2 is incor- porated by reference.

The invention relates to an illumination and displacement device for a projection exposure apparatus. Furthermore, the invention relates to an optical system comprising such an illumination and displacement device, a projec- tion exposure apparatus comprising such an optical system, a method for producing structured components by means of such a projection exposure apparatus, and a micro- or nanostmctured component, produced according to such a method. An illumination and displacement device for a projection exposure apparatus is known from WO 2009/135586 Al . Correction devices for the spatially resolved influencing of an intensity of the illumination of an illumination field are known from US 2009/0040495 Al and US 2006/0262288 Al .

It is an object of the present invention to develop such an illumination and displacement device in such a way that field-dependent imaging aberrations which are present during the projection exposure do not undesirably affect a projection result.

This object is achieved according to the invention by means of an illumination and displacement device comprising the features specified in claim 1. According to the invention, it has been recognized that the undesirable effects of field-dependent imaging aberrations on a projection result can be reduced by means of spatially resolved influencing of an intensity of the illumination over the illumination field, if the intensity of the illumination is correspondingly influenced in a spatially resolved manner. In this case, the correction device can influence the illumination intensity in a spatially resolved manner such that field regions with weaker imaging, that is to say with poorer image aberration correction, contribute to the total imaging power with smaller intensity proportions. Where the field is imag- ing-corrected well, by contrast, a higher illumination intensity is predefined by means of the correction device. The projection exposure apparatus can be operated with EUV light in the range of between 5 nm and 30 nm, in particular at wavelengths of 13.5 nm or approximately 6.9 nm. In this case, since the illumination system of an EUV projection exposure apparatus is operated in a vacuum anyway, a dedicated evacuation of the correction device can be dispensed with. As an alternative to EUV illumination, the projection exposure apparatus for which the correction device is used can also be operated with DUV light, in particular in the range of 248 nm, or with VUV light, in particular in the range of 193 nm. In this case, the correction device can be operated in a dedicated vacuum chamber, for example, which can be accommodated within the illumination system of the projection exposure apparatus. The correction device can comprise at least one optical component arranged in a projection optical unit of an optical system of the projection exposure apparatus. The effect of the correction device on the illumination intensity of the illumination field, according to which inner sections of the illumination field can be influenced without the influencing of outer sections of the illumination field surrounding said inner sections, relates in each case to one and the same instant. The effect of the correction device on the intensity of the illumination of the illumination field can be such that inner sections of the illumination field are influenced without the simultaneous influencing of outer sections of the illumination field surrounding said inner sections. In the case of a redistribution by a correction device according to claim 2, the illumination intensity is distributed such that field regions with good image aberration correction are illuminated more intensively than others. The correction device can be arranged in a field plane and/or in a pupil plane of the illumination optical unit of the illumination and displacement device. As an alternative or in addition to a redistribution of the illumination intensity, the illumination intensity can be influenced by attenuation of the illumination light.

An optical component arranged in proximity to the field according to claim 3 has a direct effect on the image aberrations in a spatially resolved manner. An optical component is in proximity to the field, that is to say arranged optically in or adjacent to a field plane, when the parameter P of the optical component in accordance with WO 2009/024164 A is at most 0.5, and in particular at most 0.1. The optical component arranged in proximity to the field can be part of a projection optical unit of an optical system of the projection exposure apparatus. The optical component arranged in proximity to the field can be an optical component which is transmissive to illumination light, that is to say which is operated refractively, in particular. A correction device according to claim 4, by means of which ejection instants for ejecting attenuating bodies are predefined, makes possible an intensity influencing of the illumination light which is suitable for EUV (extreme ultraviolet), in particular. The attenuating bodies are present as discrete bodies in terms of their trajectory. The attenuating bodies fly freely between the ejection device and the collecting device, that is to say without mechanical guidance. The attenuating bodies can attenuate the illumination light by absorption and/or scattering. The correction device can be operated in a vacuum or high vacuum, which allows good trajectory control of the attenuating bodies owing to lack of air resistance. Technological experience from the construction of ink jet printers can be used in the construction of the ejection device. The correction device is used for influencing an intensity distribution of the illumination light beam over the object field of the projection exposure apparatus. The attenuating bodies may be liquid or solid particles.

A row- or array-wise arrangement of ejection channels according to claim 5 allows a high spatial resolution of the intensity influencing over the cross section of the illumination light beam. In so far as an array of ejection channels is used in the correction device, the positions of the ejection channels in the different rows can be arranged in a manner offset relative to one another, which again increases the resolution in the dimension along the rows. The ejection channels can all run within an ejection channel plane. The trajectories of the attenuating bodies which are respectively as- signed to the ejection channels can run parallel to one another, but also at an angle with respect to one another. A course of the trajectories at an angle with respect to one another makes it possible to predefine a higher trajectory density at locations at which it should be expected that a greater attenuation of the beam intensity has to be achieved.

Independent drivability according to claim 6 allows a one-dimensional or else a two-dimensional illumination light beam cross section correction, such that a corresponding field distribution or else illumination angle distribution correction of the illumination of an illumination field or object field can occur. Droplets can be used as attenuating bodies. Droplets have proved to be suitable attenuating bodies. The droplets can be microdrop- lets. They can be mercury droplets. Alternatively, instead of droplets it is also possible for solids to be ejected, for example microparticles. The at- tenuating bodies can be ejected by the ejection device with a carrier gas or without a carrier gas. As carrier gas it is possible to use a gas which has a low absorption at a used wavelength of the illumination light. For EUV wavelengths, helium (He) can be used as a carrier gas. Alternatively, an He/N mixture or pure nitrogen (N) can also be used as a carrier gas, in par- ticular at used wavelengths higher than EUV wavelengths. The collecting device and the ejection device of the correction device can be fluid-connected to one another. Such a fluid connection makes possible a closed circuit for the attenuating body material within the correction device. In order to detect a wavefront of the illumination light beam, a measuring de- vice, which can be part of the correction device, can be signal-connected to a control device. Such a measuring device enables the correction device to be operated with closed-loop control. Predefined desired values of a field intensity distribution over an object field of the projection exposure apparatus can be predefined with closed-loop control by comparison with de- tected actual values of the field intensity distribution and corresponding driving of the correction device. Alternatively, closed-loop control can also be effected on the basis of a comparison between actual wavefront values detected by the measuring device and predefined desired wavefront values. A correction device according to claim 7 ensures that the attenuating bodies, in particular where they pass through the beam of illumination light, are not undesirably disturbed by particle impacts of a surrounding atmosphere. The ejection device and/or the collecting device can be contained in the evacuated chamber. This ensures that the complete trajectory of the attenuating bodies between the ejection device and the collecting device is not undesirably disturbed by particle impacts of the surrounding atmosphere. The configuration of the correction device with the evacuated chamber is particularly advantageous where a beam path of the illumination light beam otherwise does not run in an evacuated space. Alternatively, it is possible, in the evacuated chamber relative to pressure ratios present outside the evacuated chamber, to set pressure ratios coordinated again with the requirements of the attenuating body flight in a targeted manner. Optical sections of the correction device according to claim 8 can be embodied as an LCD array. The illumination light partial beams can then be influenced in a targeted manner by means of controlled predefmition of an absorption of the array elements. This can be done using a polarization of the illumination light.

A mirror array according to claim 9 allows a redistribution of the illumination intensity without undesirable loss of light. Alternatively, the optical sections can be made available by elements made available in a changer, which elements can be introduced into the illumination light path in a con- trolled manner.

The correction device of the illumination and displacement device according to claim 10 makes it possible to set intensity profiles along the object displacement direction which are not possible with diaphragms or neutral filters that are inserted into an illumination beam path from outside in or in proximity to a field plane. In comparison for example with uniformity influencing devices which are known as UNICOM and are described in EP 0 952 491 A2, for example, this results in new degrees of freedom when predefining intensity profiles over the illumination field. These new degrees of freedom can be used for optimizing the imaging performance and/or the throughput of the projection exposure apparatus.

The advantages of an optical system according to claim 1 1 correspond to those which have already been mentioned above with reference to the illumination and displacement device. The displacement of substrate holder with respect to object holder can be effected in the same sense or in opposite senses along the object displacement direction. An optical system according to claim 12 affords the possibility of the correction of imaging aberrations that vary over the illumination field with the aid of the correction device.

A measuring device according to claim 13 allows the illumination intensity to be influenced with feedback depending on the result of the wavefront measurement. Alternatively or additionally, the waterfront can be calculated by means of a simulation. The actual wavefront values detected and/or calculated by means of the measuring device are compared with desired wavefront values. In preparation, the effect of driving of the correc- tion device on the wavefront is detected. Depending on the result of the desired/actual comparison of the wavefront, the correction device can then be driven for closed-loop control.

The advantages of a projection exposure apparatus according to claim 14 correspond to those which have already been explained above with reference to the optical system. A changeover of the correction device in the case of a light source operating in a pulsed fashion according to claim 15 makes possible a shot-to-shot predefmition of a desired image aberration minimization. The advantages of a production method according to claims 16 to 18 and of a micro- or nano structured component according to claim 19 correspond to those which have already been explained above with regard to the projection exposure apparatus. Overall, it is possible to achieve a well defined illumination of the object during the operation of the projection exposure apparatus and thus a correspondingly high projection resolution, which results in the possibility of components produced in a finely structured manner, for example of electronic semiconductor components, e.g. of memory chips. Exemplary embodiments of the invention are explained in greater detail below with reference to the drawing in which:

Figure 1 shows schematically and with regard to an illumination optical unit in meridional section a projection exposure apparatus for projection lithography comprising an illumination and displacement device;

Figure 2 shows in an enlarged manner a correction device for influencing an intensity of an illumination light beam of an illumina- tion system of the projection exposure apparatus according to figure 1 , wherein the illumination light beam has a deviating ray direction in comparison with the illustration according to figure 1 ; shows a view of the correction device from viewing direction III in figure 2; shows a temporal intensity profile of a pulsed EUV light source of the illumination system, wherein the temporal intensity profile of one of the light pulses is illustrated in a second diagram with higher temporal resolution; shows, from a viewing direction corresponding to the viewing direction according to figure 3, a spatial distribution of attenuating bodies in the form of droplets, wherein the distributions with respect to three successive light pulses of the illumination light are specifically illustrated; shows a view of a facet arrangement of a field facet mirror of the illumination optical unit of the projection exposure apparatus according to figure 1 ; shows a view of a facet arrangement of a pupil facet mirror of the illumination optical unit of the projection exposure apparatus according to figure 1 ; shows, in an illustration similar to figure 6, a facet arrangement of a further embodiment of a field facet mirror; schematically shows a meridional section through a further embodiment of an illumination system according to the invention within a further embodiment of a projection exposure apparatus for projection lithography comprising a further em- bodiment of an illumination optical unit, which comprises a mirror array comprising tilting actuators driven by means of a controller, and a raster module comprising a two-stage raster arrangement, and also a correction device for influencing an intensity of an illumination beam of the illumination system as part of a further embodiment of an illumination and displacement device; shows a further embodiment of a correction device for influencing the intensity of the illumination beam of one of the illumination systems; and shows a further embodiment of a correction device for influencing the intensity of the illumination beam of one of the illumination systems. shows a component of a correction device for influencing a field-resolved imaging, which can be used instead of the correction device according to figure 9; shows a further embodiment of a correction device for influencing the intensity of the illumination beam of one of the illumination systems;

Figure 14 shows a further embodiment of a correction device for influencing the intensity of the illumination beam of one of the illumination systems; shows a diagram of the dependence of an imaging aberration parameter on an image field coordinate of an image field of one of the projection exposure apparatuses, said image field coordinate running parallel to an object displacement direction; shows a diagram of the dependence of an illumination intensity on the image field coordinate according to figure 15; shows, in an illustration similar to figure 16, a dependence - changed in comparison with figure 16 - of the illumination intensity over the image field coordinate; shows a diagram of the imaging aberration parameter integrated over the image field coordinate for the two illumination intensity distributions according to figures 16 and 17; shows a diagram of the dependence of the imaging aberration parameter on a further image field coordinate, which is likewise parallel to the object displacement direction; shows a diagram of the dependence of an illumination intensity on the image field coordinate according to figure 19; shows a plan view - not true to scale - of the image field of the projection exposure apparatus, wherein two scanning paths through the image field are highlighted; Figure 22 shows, in an illustration similar to figure 16, a dependence - not influenced by a correction device - of an illumination intensity on the image field coordinate according to figure 15; Figure 23 shows, in an illustration similar to figure 22, the dependence of the illumination intensity on the image field coordinate in a first influencing situation brought about by the correction device; Figure 24 shows, in an illustration similar to figure 22, the dependence of the illumination intensity on the image field coordinate in a second influencing situation brought about by the correction device; and Figure 25 shows a superposition of the dependencies according to figures 23 and 24, which allows a comparison of the intensities that are brought about by the correction device in the two influencing situations at three selected image field coordinates along the object displacement direction.

A projection exposure apparatus 1 for microlithography serves for producing a micro- or nanostructured electronic semiconductor component. The projection exposure apparatus 1 is operated in a high vacuum. A light source 2 emits EUV radiation used for illumination in the wavelength range of, for example, between 5 nm and 30 nm. The light source 2 can be a GDPP (gas discharge produced plasma) source or an LPP (laser produced plasma) source. A radiation source based on a synchrotron can also be used for the light source 2. Information concerning such a light source can be found by the person skilled in the art in US 6 859 515 B2, for example. EUV illumi- nation light or illumination radiation in the form of an illumination or imaging light beam 3 is used for illumination and imaging within the projection exposure apparatus 1. As an alternative to the use of EUV illumination light, the projection exposure apparatus 1 can also use VUV or DUV illu- mination light for the projection exposure. When VUV or DUV illumination light is used, refractive optical components can also be used instead of the reflective optical components described below. Such a projection exposure apparatus comprising VUV or DUV illumination is known from DE 10 2006 042 452 Al and WO 2009/087 805 Al .

The imaging light beam 3, downstream of the light source 2, firstly passes through a collector 4, which can be, for example, a nested collector having a multi-shell construction known from the prior art, or alternatively an el- lipsoidally shaped collector then arranged downstream of the light source 2. A corresponding collector is known from EP 1 225 481 A2. Downstream of the collector 4, the EUV illumination light 3 firstly passes through an intermediate focal plane 5, which can be used for separating the imaging light beam 3 from undesirable radiation or particle portions. After passing through the intermediate focal plane 5, the imaging light beam 3 firstly im- pinges on a field facet mirror 6.

In order to facilitate the description of positional relationships, a Cartesian global xyz coordinate system is in each case depicted in the drawing. In figure 1, the x-axis runs perpendicularly to the plane of the drawing and out of the latter. The y-axis runs toward the right in figure 1. The z-axis runs upward in figure 1.

In order to facilitate the description of positional relationships for individual optical components of the projection exposure apparatus 1, a Cartesian local xyz or xy coordinate system is in each case also used in the following figures. The respective local xy coordinates span, unless described otherwise, a respective principal arrangement plane of the optical component, for example a reflection plane. The x-axes of the global xyz coordinate sys- tern and of the local xyz or xy coordinate systems run parallel to one another. The respective y-axes of the local xyz or xy coordinate systems are at an angle with respect to the y-axis of the global xyz coordinate system which corresponds to a tilting angle of the respective optical component via the x-axis.

Figures 6 and 8 show by way of example facet arrangements of field facets 7 of the field facet mirror 6. The field facets 7 are rectangular or curved and in each case have the same x/y aspect ratio. The x/y aspect ratio can for example be 12/5, can be 25/4 or can be 104/8.

The field facets 7 predefine a reflection surface of the field facet mirror 6 and are grouped into four columns each of six to eight field facet groups 8a, 8b. The field facet groups 8a in each case have seven field facets 7. The two additional marginal field facet groups 8b of the two central field facet columns in each case have four field facets 7. Between the two central facet columns and between the third and fourth facet rows, the facet arrangement of the field facet mirror 6 has interspaces 9 in which the field facet mirror 6 is shaded by holding spokes of the collector 4. In so far as an LPP source is used as the light source 2, corresponding shading can also be produced by a tin droplet generator, which is arranged adjacent to the collector 4 and is not illustrated in the drawing.

After reflection at the field facet mirror 6, the imaging light beam 3 split into imaging light partial beams assigned to the individual field facets 7 impinges on a pupil facet mirror 10. The respective imaging light partial beam of the entire imaging light beam 3 is guided along a respective imaging light channel. Figure 7 shows an exemplary facet arrangement of round pupil facets 1 1 of the pupil facet mirror 10. The pupil facets 1 1 are arranged around a center in facet rings lying one inside another. A pupil facet 1 1 is assigned to each imaging light partial beam of the EUV illumination light 3 which is reflected by one of the field facets 7, such that a respective facet pair im- pinged upon and comprising one of the field facets 7 and one of the pupil facets 1 1 predefines the imaging light channel for the associated imaging light partial beam of the EUV illumination light 3. The channel-wise assignment of the pupil facets 1 1 to the field facets 7 is effected in a manner dependent on a desired illumination by the projection exposure apparatus 1.

Via the pupil facet mirror 10 (figure 1) and a downstream transfer optical unit 15 consisting of three EUV mirrors 12, 13, 14, the field facets 7 are imaged into an object plane 16 of the projection exposure apparatus 1. The EUV mirror 14 is embodied as a mirror for grazing incidence (grazing in- cidence mirror). Arranged in the object plane 16 is a reticle 17, from which, with the EUV illumination light 3, an illumination region is illuminated which coordinates with an object field 18 of a downstream projection optical unit 19 of the projection exposure apparatus 1. Said illumination region is therefore also designated as an illumination field 18. The imaging light channels are superimposed in the object field 18. The EUV illumination light 3 is reflected from the reticle 17. The reticle 17 is held by an object holder 17a, which is displaceable in a driven manner along an object displacement direction y during the illumination. An object holder drive 17b illustrated schematically in figure 1 serves for the driven displacement of the object holder 17a in the xy plane along the object displacement direction y.

The projection optical unit 19 images the object field 18 in the object plane 16 into an image field 20 in an image plane 21. Arranged in said image plane 21 is a wafer 22 as an example of a substrate, said wafer bearing a light-sensitive layer, which is exposed during the projection exposure by means of the projection exposure apparatus 1. The wafer 22, that is to say the substrate onto which imaging is effected, is held by a substrate holder 22a, which is displaceable along the displacement direction y synchronously with the displacement of the object holder 17a. A substrate holder drive 22b illustrated schematically in figure 1 serves for the driven displacement of the substrate holder 22a. During the projection exposure, both the reticle 17 and the wafer 22 are scanned in a synchronized manner in the y-direction. A synchronizing unit 22c serves for synchronizing the object holder drive 17b with the substrate holder drive 22b, said synchronizing unit being signal-connected to the object holder drive 17b and to the substrate holder drive 22b in a manner not illustrated in figure 1. The projection exposure apparatus 1 is embodied as a scanner. The scanning direction y is also designated as the object displacement direction.

A correction device 23 is arranged in the beam path of the illumination light beam 3 between the EUV mirror 14 and the object field 18. The correction device 23 serves for the influencing - which is spatially resolved over the object field 18 - of an intensity of the illumination light beam 3 of an illumination system 24 of the projection exposure apparatus 1. The illumination system 24 comprises the light source 2, the collector 4 and an illumination optical unit 25, which also includes the EUV mirrors 12 to 14 alongside the two facet mirrors 6 and 10. The correction device 23 influ- ences an xy intensity distribution of a cross section of an illumination light beam, as will be explained below with reference to figures 2 to 5. This intensity influencing results in an influencing of an illumination intensity distribution over the entire object field 18 or at least over sections of the object field 18. The spatial resolution of the intensity influencing by the correction device 23 is provided at least along the scanning direction y, that is to say along the object displacement direction. If the correction device 23 is used in a DUV or VUV projection exposure apparatus, the correction device 23 can be arranged in the region of a reticle masking system

( EMA) of the DUV or VUV illumination optical unit, for example directly upstream or directly downstream of a REMA diaphragm. Together with the illumination optical unit 25, the object holder 17a and the object holder drive 17b, the correction device 23 forms an illumination and displacement device for the projection exposure apparatus 1. The projection optical unit 19, the substrate holder 22a, the substrate holder drive 22b and the synchronizing unit 22c together with the illumination and displacement device form an optical system.

Furthermore, the projection exposure apparatus 1 comprises a measuring device 25a for the spatially resolved measurement of a wavefront of the imaging light 3 over the image field 20. The spatial resolution of this wave- front measurement is provided at least along the object displacement direction, that is to say along the scanning direction y. The measuring device 25a can carry out a wavefront measurement over the complete image field 20 or over a part of the image field 20 and then interpolate the measured values thus obtained to the complete image field 20. Examples of such measuring devices 25a are given in US 7,333,216 B2 and US 6,650,399 B2. Partial field or full field measurements of the wave- fronts can be performed at different, for example cyclically recurring instants. In the case of a partial field measurement over the image field 20, it is possible to use, for example, (x,y) measurement point arrays in the form of a (13, 3) array, a (13, 5) array or a (13, 7) array. It is likewise possible just to measure for example one field point (preferably the field center), three field points (preferably the field center and the field centers of the respective left and right field halves), five field points or else a different number of field points. Afterward, an extrapolation to one of the field point arrays, for example a (13, 3), (13, 5) or (13, 7) array, can then be effected. The number of measured field points can also vary from measurement instant to measurement instant. In the case of fields which, for example, are crescent-shaped or have a boundary that is different from rectangular, instead of field points in a field center or in a field half for the wavefront measurement it is also possible to use other characteristic field points, cho- sen depending on the field shape. Instead of a measurement of the wave- front over the image field 20, a simulation calculation with respect to the wavefront can also be effected, proceeding from the optical design data. In this case, the heating of the optical components carrying the illumination or imaging light 3, for example mirror or lens element heating, can be taken into account. As an alternative to a simulation calculated overall, it is possible to correct a simulation calculation model by means of customary standard methods, for example by means of a Levenberg- Marquardt algorithm, for optimizing the wavefront determination. In the context of the simulation calculation, it is also possible to use a feedforward model, for example a linear extrapolation. The simulation calculations and full field or partial field wavefront measurements over the image field 20 can be used complementarily to one another. Figures 2 and 3 show the correction device 23 in an enlarged manner in comparison with figure 1. The correction device has an ejection device 26 comprising a plurality of ejection channels 27 for attenuating bodies 28 in the form of droplets. The attenuating bodies 28 are also discrete microdrop- lets in the flight direction, that is to say droplets having a diameter in the range of between 1 μηι and 1000 μηι. The diameter of the attenuating bodies 28 can be, for example, 10 μηι, 25 μηι, 50 μηι or 100 μηι. The attenuating bodies 28 are mercury droplets. The ejection channels 27 are present in the form of micro-ejection nozzles, such as are known, in principle, in con- nection with ink jet printers. The width of an entire row of the ejection channels 27 is adapted to the width of the illumination light beam 3 in the x-direction, such that attenuating bodies 28 can fly through the entire xy cross section of the illumination light beam 3. The following holds true for the velocity v of the attenuating bodies 28: v ~ 50 m/s. Depending e.g. on the size and material of the attenuating bodies 28 and e.g. depending on ambient parameters, other velocities can also arise. The ejection channels 27 of the ejection device 26 are arranged in the form of a 3x14 array. As is evident from figure 2, three array rows are present in a manner spaced apart from one another in the z-direction. A total of 14 array columns are present in a manner spaced apart from one another in the x-direction. A different array or column arrangement of the ejection chan- nels 27 is also possible in variance of the ejection device 26, for example a column comprising M ejection channels 27 which are spaced apart from one another in the x-direction, wherein M can be in the range of between 10 and 500. Correspondingly, it is also possible to arrange one to ten channel rows, for example. By way of example, more than 1000 ejection channels 27 situated alongside one another, for example 3000 ejection channels 27, can be present in the x-direction. The channel rows adjacent to one another in the z-direction can be offset relative to one another in the x-direction in order to increase an x-resolution of the ejection device 26.

It is also possible for 100 channel rows or even more channel rows to be present. The correction device 23 is arranged in proximity to a field plane of the projection optical unit 19. From the influencing of the intensity distribution over the cross section of the illumination light beam 3, there then results a corresponding intensity distribution of the illumination of the object field 18. The intensity- influencing effect of the correction device 23 on the cross section of the illumination light beam 3, that is to say the effect of the correction device 23 on the intensity of the illumination of the illumination field 18, is such that inner sections of the illumination field 18 can be influenced without the influencing of outer sections surrounding said inner sections. Since the speed of light is very much greater than the flight velocity of the attenuating bodies 28, an illumination pulse of the illumination light beam 3 sees in each case a snapshot of a distribution of the attenuating bodies 28 over the illumination light beam 3. It is thus possible, by means of a corresponding distribution of the attenuating bodies 28, to attenuate in particular inner, central sections of the cross section of the illumination light beam 3, while for example an entire circumferential edge region of the cross section remains uninfluenced.

In an alternative arrangement of the correction device 23, the trajectory 38 of the attenuating bodies 28 through the illumination light beam 3 does not run in proximity to a field plane of the illumination optical unit 25 or of the projection optical unit 19, as in the case of the arrangement of the correction device 23 according to figure 1 , but rather in proximity to a pupil plane of the illumination optical unit 25 or of the projection optical unit 19, in particular in proximity to the pupil facet mirror 10. Such an arrangement makes it possible to achieve a defined influencing of an illumination angle distribution of the illumination of the object field 18 by using the correction device 23.

In an embodiment of the correction device 23 which is not illustrated, in- stead of droplets as the attenuating bodies 28 solids, for example micropar- ticles, are ejected by the ejection device 26 and collected by the collecting device 32. In principle, plasma or gas pulses can also be ejected as attenuating bodies. A fluid line (not illustrated in specific detail in the drawing) leads to each of the ejection channels 27. A drivable valve 29 is in each case arranged in the line path upstream of the nozzle ends of the ejection channels 27. Such a valve 29 is assigned to each of the ejection channels 27. One of said valves 29 is illustrated by way of example in figure 3. Via the valves 29, the ejection channels 27 can be driven independently of one another by a control device or open-loop/closed-loop control device 30 of the correction device 23. For this purpose, the control device 30 is signal-connected to the valves 29 of the ejection channels 27 via a multipole signal line 31, as illustrated schematically for one of the valves 29 in figure 3. The control device 30 serves for predefining ejection instants for ejecting a respective attenuating body 28 from a respective one of the ejection channels 27. This predefmition of ejection instants is also known, in principle, from the technology of inkjet printers. The control device 30 is also signal-connected to the synchronizing unit 22c, this not being illustrated in figure 1. Moreover, the control device 30 is signal-connected to the measuring device 25a, this not being illustrated in figure 1.

The correction device 23 furthermore comprises a collecting device 32 for the ejected attenuating bodies 28. On the path between the ejection device 26 and the collecting device 32, the attenuating bodies 28 fly through the illumination light beam 3, as illustrated in figures 2 and 3. In this case, figure 2 shows a part of the illumination light beam 3 in a side view, wherein a ray angle deviates from the ray angle shown in figure 1. Figure 3 shows the illumination light beam 3 in cross section.

The collecting device 32 has a collecting pan 33 and a discharge line 34 for discharging the collected attenuating bodies 28. A circulating pump 35 is arranged in the discharge line 34. Via the discharge line 34, the collecting device 32 is fluid-connected to the ejection device 26, as illustrated schematically in a dashed fashion in figure 1. In this case, the discharge line 34 is routed such that it is routed past the beam path of the illumination light beam 3. A closed circuit of the mercury forming the attenuating bodies 28 is provided via the discharge line 34.

In the embodiment according to figure 3, the measuring or detection device 25a is embodied as a linear sensor array comprising detection elements which are displaceable in the y-direction, are lined up alongside one another in the x-direction and are sensitive to the EUV light of the illumina- tion light beam 3. The detection device 25a is signal-connected to the control device 30 via a multipole signal line 37.

Figure 4 shows a temporal profile of an emission of the EUV light source 2, which is embodied as a pulsed light source. The pulse duration tau is approximately 50 ns. A pulse frequency of the light source 2 is 6 kHz. Alternatively, the pulse frequency of the light source 2 can be up to 100 kHz. In the case where a VUV light source is used instead of the EUV light source 2, the pulse duration tau is approximately 150 ns and the pulse fre- quency is 6 kHz. The temporal separation dT between two temporally successive light pulses is accordingly just under 2 ms. A duty cycle tau/dT is therefore approximately 10 ^"4 .

After being ejected from a respective one of the ejection channels 27, the attenuating bodies 28 fly on parabolic trajectories 38, the curvature of which is highly exaggerated in figure 2.

A flight velocity of the attenuating bodies 28 through the illumination light beam 3 is adapted to the pulse frequency of the light source 2.

This adaptation is such that each EUV light pulse sees an xy droplet distribution generated specially for said light pulse by means of the driving of the ejection channels 27 by the control device 30. In this case, the temporal relationship is similar to that in a stroboscope. The driving can in this case be such that each EUV light pulse sees exactly the same xy droplet distribution. This is used for example in the case of low pulse frequencies of the light source 2. Exactly identical xy droplet distributions are illustrated in figure 5 for three successive EUV light pulses N, N+l and N+2. At the instant ti considered, by way of example, an xy attenuating body distribution 39 covers the EUV light pulse N+l . Said EUV light pulse N+l is therefore attenuated two-dimensionally, that is to say in the x- and y-directions at defined points, namely where the attenuating bodies 28 are currently present. The position of the attenuating bodies 28 is predefined by corresponding temporal driving of the valves 29 of the ejection channels 27. At said instant t _{l 5} an attenuating body distribution 40 that attenuated the temporally preceding EUV light pulse N+2 has already flown a corresponding y-distance further in the direction toward the collecting device 32. At the same instant t _{l 5} a further attenuating body distribution 41 has already left the ejection channels 27 and flies toward the cross section of the illumination light beam 3 in order to be there when the succeeding EUV light pulse N arrives.

The driving in the case of the attenuating body distribution according to figure 5 is such that the EUV light pulses N, N+l and N+2 see the same attenuating body distribution.

An x-position of the attenuating bodies 28 is predefined by the driving of the valve 29 of the ejection channel 27 present in the respective column. A y-position is predefined by corresponding temporal driving of the valve 29 of the ejection channel 27. If, in the same x-position, a plurality of attenuating bodies 28 are intended to be present at different y-positions, either the same ejection channel 27 can be driven in very close succession or different ejection channels 27 of the same column, that is to say ejection chan- nels 27 which are spaced apart from one another in the z-direction and which have the same or an at least closely adjacent x-coordinate, can be driven with a corresponding temporal delay.

A density of the attenuating bodies 28 in the y-direction is therefore de- fined by an attenuating body flight time. The relationship y = dT / v holds true, wherein v is a flight velocity of the attenuating bodies 28.

In the x- and y-directions it is possible to achieve a positioning accuracy of the attenuating body distribution (cf. attenuating body distributions 39, 40, 41 in figure 5) of approximately 10 μηι. One of the ejection channels 27 can produce 25 000 of the attenuating bodies 28 per second.

The correction device 23 operates as follows: the detection device 25a measures a wavefront of the illumination light beam 3 either in a manner only spatially resolved in the y-direction or over the entire beam cross section, that is to say over the x- and y-directions. This actual wavefront is compared with a predefined desired wavefront. This comparison takes place in the control device 30. Depending on the result of this comparison, the control device 30 drives the corresponding valves 29 of the ejection channels 27 of the ejection device 26 and predefines a corresponding attenuation of the illumination light beam 3 by means of the attenuating body distribution produced over the cross section of the illumination light beam 3. The attenuating bodies 28 attenuate the EUV illumination light beam 3 in each case locally by absorption or scattering. This attenuation can be predefined in a spatially resolved manner in the y-direction or else

two-dimensionally, that is to say over the x- and y-directions in a defined manner. The method of operation of the illumination and displacement device is explained in greater detail below with reference to figures 15 to 20:

Figure 15 shows the image field dependence of an imaging aberration parameter A on the object displacement direction y along a y image field co- ordinate, that is to say for a fixed x-value x = x _t . In figure 21 , this is clarified for the schematically illustrated image field 20. The A(y) diagram in figure 15 therefore shows the profile of the imaging aberration parameter along a scanning path Si, which is also designated hereinafter as YAYE- An image of a point on the reticle 17 enters into the image field 20 during scanning along the scanning path Si at the location x y _A and emerges again from the image field 20 at the location x _l5 y _E . The imaging aberration parameter A can be a distortion or some other imaging aberration that impairs the imaging quality. Combinations and, in particular, weighted com- binations of different imaging aberrations (distortion, astigmatism, coma, spherical aberration, Petzval curvature or higher-order aberrations) are also possible. Along the scanning path Si, the imaging aberration parameter A firstly stays close to a minimum value A _min and then rises nonlinearly up to a maximum value A _max at the end of the scanning path Si. The rise in the imaging aberration parameter to values significantly greater than A _min begins along the scanning path Si above a y-value of y _F .

Figure 16 shows a first intensity scanning profile Io(y) of the illumination light 3 along said scanning path Si at x = x _t . The scanning profile has ap- proximately the form of a Gaussian distribution, wherein a minimum intensity value I _min is achieved at y = y _A and at y = y _E and a maximum intensity value I _max is achieved at (y _A + y _E )/2. The ratio I _ma x/I _m in can assume values in the range of between 1.1 and 100, in particular between 1.1 and 20. Along the scanning path portion y _F y _F , the image point of the reticle point to be imaged is impinged upon with an intensity portion of the entire intensity scanning profile which is hatched in figure 16 and is designated by I _FE . For the ratio I _FE /I _AE between the scan-integrated total intensity I _AE and the scan-integrated intensity portion I _FE , it holds true that, for example, I _FE /I _AE ≥ 0.2.

Figure 17 shows in a solid fashion the scanning profile intensity ratios I _K i(y) along the scanning path Si at x = x _t after the corrective effect of correction device 23. Along the scanning path Si, a strong intensity attenua- tion has taken place as a result of the attenuation by means of the attenuating bodies 28 in the region y _F yE- Figure 17 also illustrates in a dashed fashion the intensity profile Io(y) over the scanning profile Si without any influence of the attenuating bodies 28. The scan- integrated total intensity after influencing by the correction device is designated as I _AE , _ΚΙ ·

Since the correction device 23, by means of attenuating bodies 28, can influence the illumination light beam 3 in such a way that inner sections of the illumination field 18 can be influenced without the influencing of outer sections surrounding said inner sections, it is possible, for example, for a start and an end of the scanning path Si to remain substantially uninfluenced, whereas the illumination light beam 3 which illuminates inner sections of the illumination field 18 is attenuated. The ratio I _FE /I _AE , that is to say the proportion of that scan- integrated illumination light intensity which sees a larger imaging aberration, has decreased significantly on account of the intensity attenuation in particular in the section y _F y _E of the scanning path Si and is approximately I _FE , I _AE , _KI =

0.05.

Figure 18 illustrates the influence of the effect of the correction device 23 on the aberration A _it integrated over the scanning path Si.

The following holds true: A _s int

In the case of the scanning profile I ₀ (y) according to figure 16, the integrated scanned aberration A _int;0 is approximately double the integrated scanned aberration A _int;K in the case of the intensity scanning profile Ικι(γ) according to figure 17.

Figures 19, 20 illustrate by way of example the aberration-reducing effect of the correction device 23 in the case of a second scanning path S ₂ (cf. figure 21) at x = x ₂ . Here the imaging aberration parameter A has its maximum at (y _A +y _E )/2. Toward the two edges of the scanning path S ₂ , the imaging aberration parameter A falls in an approximately Gaussian fashion to a value A _min . The intensity scanning profile l^i ) according to figure 20 takes account of this profile of the imaging parameter according to figure 19. Said scanning profile has an intensity dip at the scanning point

(ΥΑ+ΥΕ)/2, such that the highest imaging aberration values contribute only with lower intensity. This in turn results in comparison with a Gaussian intensity impingement in accordance with figure 16 in a reduction of the scan- integrated aberration A _int .

In the same way, an aberration can also be produced in a targeted manner by variation of the scanning profile. This can be used for correction or compensation purposes, that is to say for example for correcting a wave- front aberration detected during an adjustment of the optical system or during the operation of the projection exposure apparatus.

Proceeding from imaging aberration data that are available, measured or calculated, and are spatially resolved over the image field 20, the associ- ated scanning profiles I(y), that lead to a corresponding reduction of the scan- integrated aberration can be found, for example, with the aid of the Radon transformation. For this purpose, it is possible to use suitable discretizations of an analytical inversion formula for the adjoint Radon transformation that results in the required intensity distribution I (x, y) over the field. Corresponding algorithms are described in W.H Press, S. A. Teukol- sky, W.T. Vetterling, B.P. Flannery, "Numerical Recipes in C", Cambridge University Press, 2002, chapters 3 and 4. In this case, it is possible to use convex programming algorithms that can be taken from the reference book Stephen Boyd, Lieven Vandenberghe, "Convex Optimization", Cambridge University Press, 2004, or Walter Alt, "Nichtlineare Optimierung", Vieweg, 2002 and also Frank Natterer, "The Mathematics of Computerized Tomography", John Wiley & Sons, 1986, in particular sections II.1 and II.2, pages 9 to 30. The assignment problem formulated by means of these algorithms can be solved by standard methods, e.g. sequential quadratic programming (SQP), that are part of the repertoire of conventional mathematics programs, e.g. Matlab ^® . In the course of imaging aberration minimization along the different scanning paths Si S _2. ...S _n , it is possible to take account of the secondary condition that the scan- integrated intensity is identical for each x-value. In the formulation of the assignment problem of an intensity function I(y) to an aberration function A(y), it is possible to have recourse to hierarchical target achieving specifications described in WO 2010/034674 Al . On the basis of customary design methods for the construction of projection lenses which are known from the prior art, new design methods for optics can result by using the effect of an illumination intensity scanning profile I(y) on the scanning dependence A(y) of the imaging aberration parameter. This takes account of the fact that it is possible to compensate for specific imaging aberration dependencies A(y) by way of suitable intensity scanning profiles I(y). In such design methods, firstly a standard variation of the intensity scanning profile I(y) is preselected. Afterward, a sensitivity s of the correction device is calculated by an optical design having an unvaried scanning profile, for example having the scanning profile I ₀ (y) according to figure 16, being compared with a design having a varied scanning profile Ικ( )· In this case, the sensitivity s represents a vector, wherein the individual vector coordinates represent imaging aberration parameters, for example coefficients of a development of an imaging aberra- tion, according to field-point-resolved Zernike polynomials. After difference formation has been carried out, the correction effect on the imaging aberration is assessed. The assessment or merit function can comprise additional, weighting terms. The correction device 23 is then set so as to result in the required intensity scanning profile I _K ( ) for the correction of the im- aging aberration.

By means of this manner of operation of the correction device 23, design-dictated imaging aberrations dependent on the y-coordinate of the image field 20 or else, for example thermal drifts in the illumination system 24 or in the projection optical unit 19 or an instability of the light source 2 can be corrected.

A further embodiment of an illumination system for use in a projection exposure apparatus and two further embodiments of correction devices for influencing the intensity of the illumination beam of the illumination system are described below with reference to figures 9 to 1 1. Components corresponding to those which have already been explained above with reference to figures 1 to 8 bear the same reference numerals and will not be discussed in detail again.

In the case of the projection exposure apparatus 40a according to figure 9, which can be used instead of the projection exposure apparatus 1 according to figure 1 , some optical components under figure 9 are illustrated schematically as refractive rather than reflective components. In so far as such refractive components are actually used, the projection exposure apparatus 40a is operated with illumination or imaging light 3 having wavelengths in the deep ultraviolet range (DUV or VUV). In order to facilitate the representation of positional relationships, a Cartesian xyz coordinate system is reproduced in figures 9 to 1 1. In figure 9, the x-direction runs perpendicularly to the plane of the drawing and into the latter. The y-direction runs upward in figure 9. The z-direction runs toward the right in figure 9.

A scanning direction of the projection exposure apparatus 40a runs in the y-direction, that is to say in the plane of the drawing in figure 9. In the meridional section illustrated in figure 9, the majority of the optical components of the projection exposure apparatus 40a are lined up along an optical axis 41a running in the z-direction. It goes without saying that the optical axis 41a can also be folded in ways other than that shown in figure 9, in particular in order to make the projection exposure apparatus 40a compact.

The illumination system of the projection exposure apparatus 40, said illu- mination system being designated overall by 24, serves for the defined illumination of the object field or illumination field 18 in the object plane or reticle plane 16, in which is arranged a structure to be transferred in the form of a reticle (not illustrated in more specific detail). The illumination system 24 comprises the primary light source 2 and the illumination optical unit 24 with the optical components for guiding the illumination or imaging light 3 toward the object field 18. The primary light source 2 is an ArF laser having an operating wavelength of 193 nm, the illumination light ray of which is aligned coaxially with respect to the optical axis 41. Other UV light sources, for example an F ₂ excimer laser having an operating wave- length of 157 nm, a KrF excimer laser having an operating wavelength of 248 nm and primary light sources having higher or lower operating wavelengths are likewise possible. A ray of the illumination light 3 that comes from the light source 2 and has a small rectangular cross section firstly impinges on a beam expanding optical unit 42, which generates an emerging ray of the illumination light 3 comprising substantially parallel light and having a larger rectangular cross section. The beam expanding optical unit 42 can contain elements that re- duce undesirable effects of the coherence of the illumination light 3. The illumination light 3 substantially parallelized by the beam expanding optical unit 42 subsequently impinges on a micromirror array (multi mirror array, MMA) 43 for generating an illumination light angular distribution. The micromirror array 43 has a multiplicity of rectangular individual mir- rors 44 arranged in an xy grid. Each of the individual mirrors 44 is connected to an associated tilting actuator 45. Each of the tilting actuators 45 is connected via a control line 46 to a controller 47 for driving the actuators 45. The actuators 45 can be driven independently of one another by means of the controller 47. Each of the actuators 45 can set a predefined x-tilting angle (tilting in the xz plane) and, independently thereof, a y-tilting angle (tilting in the yz plane) of the individual mirror 44, such that an angle AS _X of reflection of an illumination light partial beam 48 reflected by the associated individual mirror 44 in the xy plane and correspondingly an angle AS _X of reflection (not illustrated in the drawing) in the xz plane can be pre- defined.

The angular distribution - generated by the MMA 43 - of angles AS of reflection of the illumination light partial beams 48, upon passing through a Fourier lens element arrangement or a condenser 49 positioned at the dis- tance of its focal length from the MMA 43, is converted into a

two-dimensional illumination light intensity distribution, that is to say an illumination light intensity distribution which is location-dependent perpendicularly to the optical axis 41. The intensity distribution thus generated is therefore present in a first illumination plane 17 of the illumination system 24. Together with the Fourier lens element arrangement 49, the MMA 43 therefore constitutes a light distribution device for generating a two-dimensional illumination light intensity distribution. Arranged in the region of the first illumination plane 50 is a first raster arrangement 51 of a raster module 52, which is also designated as a fly's eye condenser. Angles of incidence E _y in the yz plane (cf. figure 9) and ER _X in the xz plane (not illustrated in the drawing) of the illumination light 3 on the raster module 52 are correlated with the angles of reflection AS _y (cf. figure 9), AS _X (not illustrated in the drawing) of the illumination light partial beams 48 from the MMA 43 and/or the location from which the respective illumination light partial beam 48 emerges from the MMA 43, that is to say the respective individual mirror 44. This correlation is predefined by the Fourier lens element arrangement 49. With the use of a Fourier lens element arrangement 49, that is to say not a condenser, the locations of impingement of the illumination light partial beams 48 on the first raster arrangement 51 are directly correlated with the angles of reflection AS _X , AS _y of the illumination light partial beams 48 from the MMA 43 since the Fourier lens element arrangement 49 approximately results in a conversion of angles into spatial coordinates. Both when a Fourier lens element arrangement 49 is used and when a condenser 49 is used, the angles of incidence ER _X , ER _y of the illumination light partial beams 48 on the raster module 52 are directly correlated with the positions of the illumination light partial beams 48 on the MMA 43, that is to say with the individual mirror 44 from which the respective illumination light partial beam 48 emerges, since both the use of a Fourier lens element arrangement 49 and the use of a condenser 49 result in a conversion of spatial coordinates into angles. The raster module 52 serves for generating a spatially distributed arrangement of secondary light sources, that is to say of images of the primary light source 2, and thus for generating a defined illumination angle distribution of the illumination light emerging from the raster module 52. A second raster arrangement 54 is arranged in a further illumination plane 53. The illumination plane 50 is in or in proximity to a front focal plane of individual elements of the second raster arrangement 54. The two raster arrangements 51, 54 constitute a fly's eye condenser of the illumination optical unit 25. The further illumination plane 53 is a pupil plane of the illumination system 24 or is adjacent to a pupil plane of the illumination system 24. The raster module 52 is therefore also designated a field defining element (FDE).

Angles of reflection A _y in the yz plane (cf. figure 9) and AR _X in the xz plane (not illustrated in the drawing) at which the illumination light partial beams 48 leave the second raster arrangement 54 are uniquely assigned to a spatial region in the object field 18 on which the respective illumination light partial beam 48 impinges on the object field 18. Disposed downstream of the raster module 52 is a further condenser 55, which is also designated as a field lens element. Together with the second raster arrangement 54 the condenser 55 images the first illumination plane 50 into a field intermediate plane 56 of the illumination system 24. A reticle masking system (REMA) 57 can be arranged in the field intermediate plane 56, said system serving as an adjustable shading diaphragm for generating a sharp edge of the illumination light intensity distribution. A downstream lens 58 images the field intermediate plane 56 onto the reticle, that is to say the lithography original, which is situated in the reticle plane 16. By means of the projection lens 19, the reticle plane 16 is imaged onto the wafer or image plane 21 onto the wafer (not illustrated in figure 9), which is intermittently or continuously displaced in the scanning direction

(y). The raster construction and the function of the raster module 52 correspond, in principle, to what is described in WO 2007/093433 Al and in WO 2009/135586 Al .

The field intermediate plane 56 coincides with an ejection channel plane of a correction device 59 for the two-dimensional influencing of the intensity of the illumination light beam 3. The function of the correction device 59 corresponds to that of the correction device 23 already explained above in connection with figures 1 to 8. Components of the correction device 59 which correspond to those of the correction device 23 already explained above bear the same reference numerals and will not be discussed in detail again.

Only an entrance window 60 and an exit window 61 of the correction device 59 are illustrated in figure 9; further details of said correction device will become apparent with reference to figure 10.

Both the entrance window 60 and the exit window 61 are transmissive to the illumination or imaging light 3. Part of the correction device 59 is an evacuated chamber 62, through which runs the trajectory of the attenuating bodies 28 between the ejection device 26 and the collecting device 32. The entrance window 60 and the exit window 61 are inserted in a pressure-tight fashion into chamber walls of the evacuated chamber 62. The ejection device 26 and the collecting device 32 are contained in the evacuated cham- ber 62.

The discharge line 34 and a return of the attenuating body material from the collecting device 32 toward the ejection device 26 are not illustrated in figure 10. Such a return can be routed within the evacuated chamber 62 or leads through pressure-tight passages through the chamber walls.

The ejection channel plane 56 is perpendicular to the plane of the drawing in figure 10. In said ejection channel plane, the trajectories 38 of the ejection channels run parallel to one another. In figure 10, the trajectories 38 run vertically from top to bottom.

By means of a control of the ejection instants for the attenuating bodies 28 of the different ejection channels, an intensity distribution of the illumination light beam 3 in the field intermediate plane 56 and thus a correspond- ing intensity distribution in the object plane 16 can once again be predefined two-dimensionally. In this case, the correction device 59 also has an effect on the intensity of the illumination of the illumination field 18 such that inner sections of the illumination field 18 can be influenced without the influencing of outer sections surrounding said inner sections.

The correction device 59, the illumination optical unit 25 and the object holder (not illustrated in figure 9) for mounting a reticle in the object plane 16 and an object holder drive corresponding to the components 17a, 17b of the embodiment according to figure 1 constitute a further embodiment of the illumination and displacement device in the embodiment according to figure 9.

The projection exposure apparatus 40 can also in turn comprise a measur- ing device corresponding to the measuring device 25a of the embodiment according to figure 1 for measuring a wavefront over the mirror field 20 in the image plane 21. The projection optical unit 19 and a wafer substrate holder (not illustrated in figure 9) with substrate holder drive and a synchronizing unit (likewise not illustrated in figure 9) for synchronizing the object holder drive with the substrate holder drive together with the illumination and displacement device constitute an optical system.

The correction device 59 can also be used in the projection exposure apparatus 1 according to figures 1 to 8. Accordingly, the correction device 23 according to figures 1 to 8 can also be used in the projection exposure apparatus 40 according to figure 9.

Figure 1 1 shows a further embodiment of a correction device 63, which can be used instead of the correction devices 23 and 59, respectively.

The ejection channel plane 56 runs in the plane of the drawing in figure 1 1. The ejection channel plane 56 can once again coincide with the field intermediate plane of the illumination system 24 according to figure 9 or can be adjacent to the object plane 16, as in the embodiment according to figures 1 to 8. A plurality of ejection channel planes 56 spaced apart from one another in the z-direction can also be present. A ray direction of the illumination light beam 3 runs perpendicularly to the plane of the drawing in figure 1 1. The ejection device 26 of the correction device 63 is subdivided into a plurality of partial ejection units 64, which in each case eject the attenuating bodies 28 from an ejection channel 27 along a trajectory 38 within the ejection channel plane 56. Figure 1 1 illustrates by way of example a plurality of the partial ejection units 64 and the ejection channels 27 thereof and the trajectories 38 of the attenuating bodies 28 ejected via said ejection channels 27. By means of the different partial ejection units 64, the attenuating bodies 28 are therefore injected from different marginal points at a plurality of injection angles.

The partial ejection units 64 are arranged in a manner distributed around the illumination light beam 3. Only some of the partial ejection units 64 are illustrated in figure 1 1. In actual fact, so many of the partial ejection units 64 are arranged around the cross section of the illumination light beam 3 that the trajectories 38, partly with higher, partly with lower trajectory density, reach practically every location within the cross section of the illumination light beam 3 in the ejection channel plane 56.

Each of the partial ejection units 64 is assigned a corresponding partial col- lecting unit of the partial collecting device 32 for the attenuating bodies 28. Said partial collecting units, in the same way as the discharge lines for the attenuating material and possibly return to the partial ejection units, are not illustrated in figure 1 1. By means of the partly crossing trajectories 38 of the ejection channels 27 of the partial ejection units 64 of the correction device 63, said trajectories being injected at different angles, a

two-dimensional intensity distribution of the illumination light beam 3 can be predefined by means of the respective local attenuation of the illumination light beam 3 by the attenuating bodies 28 in a defined manner, analo- gously to what has already been explained above in connection with the correction device 23 according to figures 1 to 8.

Figure 12 shows a further component of a correction device 65, which can be used with the further components of the correction devices 23, 59 or 63. The correction device 65 has as an additional component a correction element in proximity to the field in the form of an aspherized plane plate 66. The plane plate 66 is composed of material transparent to the illumination and imaging light 3. One of the two optical surfaces, a rear side 67 in the case of the arrangement according to figure 12, is embodied in plane fashion. The other of the two optical surfaces of the plane plate 68, the front side 68 in the case of the arrangement according to figure 12, is embodied in aspherized fashion with a refractive power that varies along the y-direction. This is illustrated schematically in the enlarged excerpt in fig- ure 12. The plane plate 66 is part of the projection lens 19.

The aspherized plane plate 66 can be arranged in a plane 16' in proximity to the object plane 16. Such an arrangement is also designated as an arrangement in proximity to the field. The parameter P known from WO 2009/024164 A can be used for evaluating the field proximity. P < 0.5 and in particular P < 0.1 holds true for the aspherized plane plate.

The aspherized plane plate 66 has a great variation of the imaging aberration parameter A(y) along the scanning direction y. With the aid of aspher- ized plane plate 66, y-dependencies of the imaging aberration parameter can be impressed on the wavefront of the illumination light 3 in a spatially resolved manner, for which dependencies a good compensation is provided by predefmition of a corresponding intensity scanning profile I(y). Possibly unfavorable distributions A(y) of the imaging aberration parameter that are present on account of the optical design without the aspherized plane plate 66 can in this way be converted into dependencies that are more suitable for compensation by predefmition of a corresponding scanning profile intensity distribution I(y).

The aspherized plane plate 66 brings about a redistribution of the intensity of the illumination light 3 along the object displacement direction y at least in sections of the object field 18. The plane plate 66, too, can be designed with such an effect on the intensity of the illumination of the illumination or object field 18 in such a way that inner sections of the illumination field 18 can be influenced without the influencing of outer sections of the illumination field 18 surrounding said inner sections.

Figure 13 shows a further embodiment of a correction device 69, which can be used instead of the correction devices 23, 59, 63 or 65.

The correction device 69 is embodied as an xy array composed of liquid crystal (LCD) elements 70, which, by means of an open-loop/closed-loop control device 71, the function of which corresponds to that of the control device 30, can be driven individually for the predefmition of a transmission of the respective liquid crystal elements 70 for the illumination and imaging light 3. The liquid crystal elements 70 are connected to an optical unit carrier, indicated schematically as a frame 70a in figure 13. The liquid crystal elements 70 can be switched between a transmissive and an absorbent state. Alternatively, it is also possible to predefine a transmission in a continuum between a maximum and a minimum transmission of the respective liquid crystal elements 70. The function of the correction device 69 corresponds to that of the correction device 23, wherein the attenuating bodies 28 are replaced by liquid crystal elements 70 switched to be correspondingly (partly) absorbent.

The correction device 69 is constructed as an ij array, wherein i and j can be in the range of between 2 and 1000 or even greater.

The setting of an absorption by means of the liquid crystal elements 70 can be effected using a linear polarization of the illumination light 3. The correction device 69, too, can be embodied such that inner sections of the illumination field 18 can be influenced without the influencing of outer sections of the illumination field 18 surrounding said inner sections.

A further embodiment of a correction device 72, which can be used instead of the correction devices 23, 59, 63, 65 or 69, is described below with reference to figure 14. Components corresponding to those which have already been explained above with reference to figures 1 to 13 and 15 to 20, in particular with reference to figure 9, bear the same reference numerals and will not be discussed in detail again.

The correction device 72 in the form of a mirror array, in particular an MMA 74, is arranged in a pupil plane 73 of the illumination optical unit 25. Analogously to the MMA 43, the MMA 74 comprises a plurality of individual mirrors 75 which can be tilted by means of respectively assigned actuators 76, controlled by means of a control device 77 in the manner of the controller 47. The individual mirrors 75 are in each case connected to a mirror carrier (not illustrated in more specific detail), that is to say to an optical unit carrier. Figure 14 illustrates a light path 48o of an illumination light partial beam 48 in an initial position of one of the individual mirrors 75 ₁ and a light path 48 _K of the same partial beam 48 in the tilting position of the individual mirror 75 ₁ as illustrated in figure 14. There is a resulting shift in the illumina- tion intensity over the object field 18. The effect of this shift is illustrated in a dash-dotted fashion in figure 17. Instead of the initial intensity distribution Io(y), the result now is a shifted intensity distribution Ικ2(γ) depicted in a dash-dotted fashion. Since no illumination light is lost as a result of attenuation or absorption, the effect of a tilting of the individual mirrors 75 and a corresponding redistribution of the illumination intensity over the object field 18 result in a further improved effect of the correction device 72. In the case of the example illustrated in figure 17, the ratio I _AE , _K 2 / I _FE is increased relative to the already discussed ratio produced by attenuation by means of the attenuating bodies 28 of the correction device 23 and the ab- erration correction is thus improved.

The correction device 72, too, can be embodied such that inner sections of the illumination field 18 can be influenced without the influencing of outer sections of the illumination field 18 surrounding said inner sections.

With the aid of the illumination set by the correction device 23, 59, 63 or 65, 69 or 72, structured components, in particular semiconductor components in the form of microchips, for example memory chips, can now be produced by means of the projection exposure apparatus 1 or 40, respec- tively. For this purpose, the wafer 22 is provided, on which a layer composed of a light-sensitive material is at least partly applied. Moreover, the reticle 17 comprising the structures to be imaged is provided. By means of the projection exposure apparatus 1, at least one part of the reticle 17 is then projected onto a region of the layer of the wafer 22. The micro- or na- nostmctured component is then produced by developing the light-sensitive layer.

The correction devices 23, 59, 63, 65, 69 or 72 can have an effect over the entire object field 18 or alternatively over one or more sections of the object field 18. A corresponding effect arises over the image field 20.

Instead of the liquid crystal elements 70, which are individually switchable, it is possible to make available array arrangements composed of transmis- sive raster elements with given absorption absorbent raster elements in a changer, wherein a respectively desired distribution of transmissive and absorbent raster elements for predefining an intensity distribution I(y) can be generated by inserting the respective raster. The correction devices 23, 59, 63, 69 or 72 can be designed, in the case of a pulsed manner of operation of the light source 2, such that a changeover of the respective correction device 23, 59, 63, 69 is effected for the pre- defmition of different illumination intensity distributions I(y) which are spatially resolved along the object displacement direction y over the illu- mination or object field 18 between individual light pulses of the light source 2 that are used for the illumination.

The possibilities of influencing the illumination intensity I depending on the image field coordinate y, that is to say depending on the coordinate along the object displacement direction, are elucidated again below with reference to figures 22 to 25. This effect can be achieved with any of the correction devices described above, that is to say in particular with the correction devices 23, 59, 63, 65, 69 or 72 illustrated in the drawings. This is illustrated below on the basis of the example of the effect of the correction device 23. Figure 22 shows the ideal case of field illumination uninfluenced by the correction device 23. An illumination intensity I = I ₀ arises at all three field points yi = y _A , y ₂ and y ₃ = y _E . The three field points y _{l 5} y ₂ and y ₃ are situated equidistantly with respect to one another.

Figure 23 shows the effect of the correction device 23 in a first influencing situation, that is to say in the case of a first distribution of the droplets 28 along the y-coordinate or, for example in the case of a different variant of the correction devices described above, in the case of a different mirror tilting position. At the coordinate y _{l s} the illumination intensity I _t (y _t ) arises, that is to say an intensity which, at the first of the three object field points yi, y ₂ , y ₃ along the object displacement direction, deviates by a first influencing intensity factor kl from the uninfluenced intensity I ₀ of the first object field point y _t . For the influencing intensity factor kl the following holds true: kl = I _t (y _t ) / 1 ₀ . In this first influencing situation, an intensity i! (y ₂ ) results from the effect of the correction device 23 at the second object field point y ₂ along the object displacement direction. Said intensity deviates by a second influencing intensity factor k2 from the uninfluenced intensity I ₀ at the second object field point (y ₂ ). The following holds true: k2 = Ii (y ₂ ) / LQ. The following additionally holds true: kl≠ k2. Figure 24 shows the intensity ratios in the case of a second influencing situation of the correction device 23, that is to say in the case of an influencing situation changed over in comparison with the first influencing situation. In this situation there is now a different distribution of the droplets 28 along the y-coordinate or, in the case of a different embodiment of the correction device, for example a different mirror tilting position.

The intensity influencing at the first object field point y _t in the second in- fluencing situation is of no further interest at this juncture. At the second object field point y ₂ along the object displacement direction y ₂ , the illumination intensity I ₂ (y ₂ ) achieved in the second influencing situation deviates from the uninfluenced intensity I ₀ once again exactly by the first influencing intensity factor kl . The following therefore holds true: I ₂ (y ₂ ) = kl x I ₀ . Furthermore the following holds true: Ii (y _t ) = I ₂ (y ₂ ).

In the second influencing situation of the correction device 23, the intensity ( 3) at the third object field point y ₃ furthermore deviates by a third influencing intensity factor K3 from the uninfluenced intensity I ₀ . The fol- lowing therefore holds true: I ₂ (y ₃ ) = k3 x I ₀ . On account of the free adjustability of the correction device 23, k3≠ k2 holds true. The following therefore holds true: Ii (y ₂ ) = I ₂ (y ₃ ). The illustration there shows in a solid fashion the intensity profile Ii along the y-coordinate of the first illumination situation and in a dashed fashion the intensity profile I ₂ along the y- coordinate in the second influencing situation of the correction device 23. The dashed I ₂ curve does not attain the value Ii (y ₂ ) at the object field point y ₃ , rather the following holds true: I ₂ (y ₃ ) < Ii (y ₂ ).

The superiority of the correction device 23 is manifested here with regard to the adjustable degrees of freedom of intensity influencing by means of the y-coordinate in comparison with, for example, a neutral filter that can be inserted along the y-coordinate. With such a neutral filter it would only be possible to achieve intensity influencing I ₂ ' in the second influencing situation which is continued in a dash-dotted fashion in the region of the third object field point y ₃ in figure 25. Said intensity influencing I ₂ ' necessarily attains the value I ₂ ' (y ₃ ) = Ii (y ₂ ) at the object field point y ₃ . For such a neutral filter that is not according to the invention, therefore, the inequality Ii (y ₂ )≠ I ₂ (y ₃ ) cannot hold true.