Apparatus and method for controlling temperature of elements in microlithographic projection exposure systems

Abstract

The invention relates to a microlithographic projection exposure system, in particular for the DUV range (400) or the EUV range (100), comprising an illumination unit (102; 402) and a projection lens (104, 340, 640; 404) having at least one element (370, 372, 380, 382, 390, 396, 397, 399, 391, 392, 393, 394, 398, 451, 930, 1010, 1012, 1014).404), the at least one element is at least regionally penetrated by at least one temperature-controlled fluid line (302, 304, 306, 308, 310, 452, 476, 486, 602, 919, 921, 1007), the at least one temperature-controlled fluid line being provided for conducting temperature-controlled fluid to control the temperature of the element, wherein the temperature-controlled fluid line (302, 304, 306, 308, 310, 452, 476, 486, 602, 919, 921, 1007) is connected to at least one temperature-controlled fluid storage container (470, 480, 61). 5,515,516,519,460,920,1020), and wherein at least one temperature control element (702,704,706,906,916,1006) for controlling the temperature of the temperature control fluid is disposed on or in the temperature control fluid line (302,304,306,308,310,452,476,486,602,919,921,1007), wherein at least two elements (370,372,380,382,390,396,397,399,391,392,393) are disposed on or in the temperature control fluid line. 394, 398, 451, 930, 1010, 1012, 1014) are independently penetrated by at least one individual temperature-controlled fluid line (302, 304, 306, 308, 310, 452, 476, 486, 602, 919, 921, 1007), or at least two distinct regions of at least one element (370, 372, 380, 382, ​​390, 396, 397, 399, 391, 392, 393, 394, 398, 451, 930, 1010, 1012, 1014) are independently penetrated by at least one individual temperature-controlled fluid line. A temperature-controlled fluid line (302, 304, 306, 308, 310, 452, 476, 486, 602, 919, 921, 1007) penetrates the system, or at least two elements (370, 372, 380, 382, ​​390, 396, 397, 399, 391, 392, 393, 394, 398, 451, 930, 1010, 1012, 1014) are penetrated by the temperature-controlled fluid line (302, 304, 306, 308, 310, 452, 476, 486, 602, 919, 921, 1007). The invention also relates to a method for controlling the temperature of at least one element in a microlithography projection exposure system (300, 400).

Description

Technical Field

[0001] This invention relates to equipment for controlling the temperature of components in a microlithography projection exposure apparatus. Furthermore, this invention relates to a method for controlling the temperature of components in a microlithography projection exposure apparatus. Background Technology

[0002] Microlithography is used to produce microstructured components, such as integrated circuits or LCDs. The microlithography process is performed in a so-called projection exposure apparatus, which includes an illumination device and a projection lens. Here, an image of a mask (=mask master) illuminated by the illumination device is projected through the projection lens onto a substrate (e.g., a silicon wafer) coated with a photosensitive layer (=photoresist), and the substrate is arranged in the image plane of the projection lens so that the mask structure is transferred onto the photosensitive coating of the substrate.

[0003] The terms microlithography projection exposure apparatus, projection exposure apparatus, (EUV or DUV) system, and lithography scanner are used synonymously in the following text.

[0004] In projection lenses designed for the DUV range, i.e., at wavelengths of, for example, 193 nm or 248 nm, lens elements are preferably used as optical elements for the imaging process. For achieving higher resolution lithography optics, projection lenses designed for the EUV range, operating at wavelengths of, for example, approximately 13.5 nm or 7 nm, have been used for many years.

[0005] In such projection lenses designed for the EUV range, mirrors are used as optical elements for the imaging process due to the lack of suitable light-transmitting and refractive materials. These mirrors operate with near-perpendicular or grazing incidence. Because of the mirror's reflective properties, it is far more sensitive to position than a lens element. In this respect, the tilt of a mirror translates to a change in the direction of light by a factor of 2, whereas in the case of a lens element, what typically occurs is a considerable compensation for the change in the direction of refracted light between the front and back surfaces.

[0006] The significant influence on the shape of a mirror stems from the thermal expansion of the mirror material. Therefore, materials with low coefficients of thermal expansion, such as Zerodur or ULE (ultra-low expansion), are used in EUV mirrors. These materials are much less responsive to temperature changes than glass or quartz glass. However, a considerable error contribution can still occur within the available aberration budget. This error contribution consists of the effects of non-uniform temperature distribution within the material volume and non-uniformity at the so-called zero-crossing temperature (ZCT), for example, due to stoichiometric variations between SiO2 and TiO2 in ULE materials. Both local and global temperature variations relative to the intended operating temperature of the microlithography projection exposure apparatus contribute to aberrations, which can only be partially corrected by manipulators.

[0007] Operating conditions are typically defined by the assumed maximum power of the EUV system at the operating wavelength, i.e., for example, at a wavelength of 13.5 nm. If the maximum power is not reached, for example because a mask master with a low average reflectivity is used, then, according to existing technology, an infrared heater can achieve "supplementary" heating and ensure that the mirror operates at a temperature close to the average zero-crossing temperature, where the mirror is particularly insensitive because secondary deformation depends on the temperature difference relative to that temperature.

[0008] To transfer heat away from the projection lens, and very generally to provide suitable temperature control for the elements of the projection lens, a temperature-controlled fluid, typically water, is used, flowing at least locally through the system. Thus, Figure 1 illustrates an EUV projection lens 640 according to the prior art. The force frame 381, which carries the EUV mirrors 691, 692, 693, and 694, employs overall temperature control of the EUV projection lens through its water cooling. Only a single temperature-controlled fluid line 602 runs through the entire force frame 381. The four EUV mirrors 691, 692, 693, and 694 are connected to the force frame 381 via an active mechanical bearing 695. A sensor frame 371 serves as a reference for position measurement 625 of the EUV mirrors 691, 692, 693, and 694. An exemplary heat flow Q1 in the direction of the sensor frame 371 and an exemplary heat flow Q2 in the direction of the mirror 692 are depicted. EUV light 502 from the structural support mask 120 (not shown in Figure 1) is reflected by four EUV mirrors 691, 692, 693, and 694 and guided as EUV light 504 to wafer 124 (not shown in Figure 1). A temperature-controlled fluid line 602 guides temperature-controlled fluid through force frame 381. The temperature-controlled fluid line 602 is supplied by a temperature-controlled fluid storage container 615 for force frame 381. A temperature control element 702 is arranged downstream of the force frame temperature control inlet 607. A temperature sensor 802 is arranged in force frame 381. The temperature sensor 802 is coupled to the temperature control element 702. For clarity, coupling and closed-loop control are not depicted in Figure 1 (see [reference needed] for details). Figure 2 After flowing through the temperature-controlled fluid line 602, the temperature-controlled fluid reaches the fluid storage container 615 via the force frame temperature control outlet 614. If the temperature control element 702 is designed for simplicity to be capable only of heating, it is necessary to integrate a so-called recooler system or equivalent recooler unit into the device. Without this recooler system, the temperature-controlled fluid will continue to be heated. A recooler system is a device that dissipates excess heat from the system through a heat exchanger. For clarity, this recooler system is not shown in Figure 1.

[0009] During this process, the temperature control of the force frame 381 employs the following task:

[0010] - The thermal stability of the force frame structure was initially used to stabilize the positioning mirror. Rigid body motion can be compensated for by actuators. However, due to the deformation of the mirror, the forces transmitted from the actuators to the mirror will produce wavefront aberrations. Furthermore, the additional power dissipated in the actuator unit may cause thermal drift in optical imaging.

[0011] - Thermal stability around the mirror. Heating around the mirror can cause wavefront aberration. This is due to mirror deformation caused by deviations in mirror temperature from the design temperature (zero-crossing temperature) and by deviations between production and measurement temperatures.

[0012] - The shielded sensor frame (=reference for mirror positioning) is protected from thermal loads (such as mirror preheating, actuator, encoder and sensor waste heat) to prevent deformation of the measurement reference.

[0013] - Closed-loop thermal control of the sensor frame to bring the sensor frame from a thermally uncontrolled state to a stable, temperature-controlled operating state. This is necessary, for example, within the range of system recovery.

[0014] - Closed-loop thermal control is applied to the sensor frame during operation to keep it within tolerances for absolute temperature and temperature drift (the derivative of the sensor frame temperature with time).

[0015] Considering the heating of the structure (force frame, sensor frame) and the mirror, the above five requirements related to the temperature control of the force frame could only be met through compromises in the thermal architecture.

[0016] Figure 5 shows a DUV projection lens according to the prior art. A temperature-controlled fluid line 452 passes through a cooler and a sensor housing 450. A temperature-controlled fluid line inlet 454 and a temperature-controlled fluid line outlet 456 establish a connection to a DUV temperature-controlled fluid storage container 460. A temperature sensor 806 is coupled to a temperature control element 706. For clarity, Figure 6 Coupling and closed-loop control are not depicted. A cooler and sensor housing 450 at least partially surrounds the DUV projection lens 404. Q5 is used to depict the heat flow to the user in an exemplary manner, while Q6 is used to depict the heat flow from the projection lens 404. The DUV light at the entrance of the DUV projection lens 404 is marked 408. The DUV light reaching the wafer 424 (not depicted in FIG. 5) is marked 458.

[0017] Only a single temperature control fluid line 452 passes through the cooler and sensor housing 450. This cannot be used to keep different areas of the cooler and sensor housing 450 at different temperature levels. This is also a compromise.

[0018] In view of the above problems, the purpose of this invention is to provide an apparatus and method for solving these problems, in particular to improve the thermal stability of a photolithography system. Summary of the Invention

[0019] According to the invention, the above-mentioned objective is achieved by a microlithography projection exposure apparatus, particularly for the DUV or EUV range. The projection exposure apparatus includes an illumination device and a projection lens having at least one element, which is at least regionally used to guide at least one temperature-controlled fluid line through for temperature control of the element. The temperature-controlled fluid line is connected to at least one temperature-controlled fluid storage container, and at least one temperature control element for controlling the temperature of the temperature-controlled fluid is disposed at or within the temperature-controlled fluid line. In this configuration, at least two elements are independently traversed by at least one separate temperature-controlled fluid line, or at least two different regions of at least one element are independently traversed by at least one separate temperature-controlled fluid line, or at least two elements are traversed by temperature-controlled fluid lines. These three options are particularly advantageous because they allow for different temperatures in different elements or different regions of a single element.

[0020] In one embodiment, at least two separate temperature control loops are connected in parallel with each other. This is advantageous because it allows for independent temperature control of different components or different regions of a single component. Using this, different regions of a component (e.g., a force frame) can be maintained at different temperatures. Therefore, this provides the option of providing different supply temperatures to individual regions. A general goal is to avoid distributing heat flow incorporated into the temperature control fluid on one side of the component throughout the system.

[0021] In one embodiment, the two temperature control loops are supplied by a common temperature control fluid storage container. This is advantageous because it reduces installation space requirements.

[0022] In one embodiment, the two temperature control loops are supplied by separate temperature control fluid storage containers. This is advantageous because it allows for particularly precise setting of the temperature control fluid in the respective temperature control fluid lines.

[0023] Preferably, the temperature control fluid in the temperature control fluid storage container is maintained below the target temperature of the element to be temperature controlled. This makes a pure heater sufficient as the temperature control element. Cooling of the temperature control fluid is unnecessary. The heater is arranged at the outlet of the temperature control fluid storage container and / or at the inlet of the element to be temperature controlled. If the temperature control element 702 is only capable of heating, it is necessary to integrate a so-called recooler system or a synonymous recooler unit into the device. Without this recooler system, the temperature control fluid will be continuously heated.

[0024] The temperature control element can be located outside the vacuum, that is, away from the temperature control fluid lines where the element to be controlled is located. This is advantageous because the heater will not interfere with the interior of the projection lens. However, if the element needs to maintain a very precise temperature, it is necessary to place the heater as close to the element as possible. This also reduces transportation interference.

[0025] It is necessary to measure the spatial temperature distribution of large components (such as force frames); that is, for example, at least two temperature sensors must be installed and evaluated for each component.

[0026] In one embodiment, at least two elements are connected in series and passed through the same temperature-controlled fluid line. This is particularly advantageous because it represents a particularly simple and space-saving solution.

[0027] In one embodiment, at least one temperature sensor is provided in each element for measuring the temperature at or within the element. The purpose is to use the temperature sensor to measure the element to be temperature controlled. Depending on the control task, the temperature sensor is attached to those locations that measure the quantity to be regulated as representatively as possible. For example, determining the average temperature, spatial temperature gradient, or temporal temperature gradient. Inlet and outlet temperatures can also be measured to measure the emitted or received heat flow. Within the element, the temperature sensor should not be placed too close to the temperature control fluid line to ensure that measurements representative of the element's thermal state are obtained.

[0028] In one embodiment, at least one controller is provided for closed-loop control of the temperature control element, particularly based on the temperature measured by a temperature sensor at or within the element.

[0029] However, the element can also be temperature-controlled without closed-loop control. In this case, due to low thermal resistance (large cooler surface area and / or high heat transfer coefficient between the temperature control fluid and the element) and the highest possible heat capacity flow (high water flow rate and / or high fluid heat capacity), the temperature of the corresponding element approaches the water temperature, and thus the reference temperature. Furthermore, the spatial distribution of the cooling lines reduces the temperature gradient within the element. Therefore, high-frequency interferences above the control bandwidth of the thermal control loop for element cooling, and the associated element deformation, can be greatly suppressed.

[0030] In one embodiment, the element is implemented as follows:

[0031] -As at least one sensor frame

[0032] -As at least one force frame

[0033] - As a support frame for at least one reflector

[0034] - As at least one reflector, and / or

[0035] - As at least one cooler and heat shield.

[0036] In one embodiment, at least one cooler and heat shield (particularly with active temperature control and / or particularly with passive temperature control) are arranged between at least two elements, particularly between the force frame and the sensor frame. This is particularly advantageous because the cooler and heat shield can suppress thermal interference particularly effectively. Thus, high-frequency interference with a time constant of less than one hour can be suppressed by shielding the sensor frame. Temperature-controlled fluid flows through the active cooler and heat shield. The temperature-controlled fluid removes the system's heat output. The active cooler and heat shield act as a radiator. A cooler and heat shield with passive temperature control can delay and mitigate the thermal effects caused by the heat load on the sensor frame. However, they merely form a resistance, directing heat in another direction. Therefore, the passive shield directs the heat flow to the active shield, which ultimately removes the system's heat output. Passive closed-loop control literally means providing a constant water temperature without control. However, the temperature setpoint of an element with passive closed-loop control may also be changed due to active closed-loop control of other elements. Active closed-loop control refers to at least one feedback controller controlling the inlet temperature.

[0037] Coolers and heat shields deliver water through tiny gaps. They are typically made of steel, aluminum, or ceramic. Coolers and heat shields have high thermal conductivity.

[0038] In one embodiment, the EUV light beam path and at least one reflector are housed by at least one cooler and heat shield, particularly with active temperature control.

[0039] In one embodiment, the temperature-controlled fluid storage container and temperature control element are arranged outside the projection lens. This is advantageous because it avoids introducing additional heat load into the projection lens.

[0040] According to the invention, the above objective is further achieved by a method for controlling the temperature of at least one element in a microlithography projection exposure apparatus provided for EUV or DUV range. At least one temperature control fluid line is provided for guiding temperature control fluid through at least one element, which at least one element is temperature-controlled using at least the following steps:

[0041] - Define the target temperature for at least one component.

[0042] -Measure the actual temperature of at least one element by at least one temperature sensor at or within at least one element.

[0043] - The actual temperature is compared with the target temperature using a comparator element.

[0044] - The deviation between the actual temperature and the target temperature is read into the controller.

[0045] - The temperature of the temperature-controlled fluid is controlled by at least one temperature control element located at or in at least one temperature-controlled fluid line until the deviation between the actual temperature of the element and the target temperature is below a specified limit.

[0046] The same method can also be applied to different temperature control in different areas of a single component. Attached Figure Description

[0047] Various exemplary embodiments are explained in more detail below with reference to the accompanying drawings. The relative sizes of the elements shown in the drawings and figures should not be considered as drawn to scale. Rather, for better understanding, individual elements may be shown enlarged or reduced in size to allow them to be better represented.

[0048] Figure 1 shows a schematic diagram of an EUV projection lens in the prior art.

[0049] Figure 2 A schematic diagram of components from an EUV system for temperature control according to the present invention is shown.

[0050] Figure 3 A schematic diagram of EUV projection lenses with parallel connections according to the present invention is shown.

[0051] Figure 4 A schematic diagram of EUV projection lenses connected in series according to the present invention is shown.

[0052] Figure 5 shows a schematic diagram of a DUV projection lens in the prior art.

[0053] Figure 6 A schematic diagram of a DUV projection lens according to the present invention is shown.

[0054] Figure 7 The microlithography projection exposure apparatus provided for the EUV range is shown.

[0055] Figure 8 The microlithography projection exposure apparatus provided for the DUV range is shown. Detailed Implementation

[0056] Figure 2 A schematic diagram of an element 930 from an EUV system for temperature control according to the present invention is shown. This is a parallel connection 900 of two temperature control loops. For example, element 930 may be a sensor frame, a force frame, or a mirror support frame. A temperature control fluid line 919 passes through the lower region of element 930. A temperature control fluid line 921 passes through the upper region of element 930. A temperature sensor 907 measures the temperature of the lower region of the element and transmits the measured temperature value to a controller 902, which controls a temperature control element 906 located at the temperature control fluid line 919. The temperature control fluid line 919 is supplied by a temperature control fluid storage container 920 and includes a temperature control fluid inlet 904 and a temperature control fluid outlet 908. If the temperature control element 906 is designed for simplicity to only be able to heat, it is necessary to integrate a so-called recooler system or a synonymous recooler unit into the device. Without this recooler system, the temperature control fluid will continue to be heated. For clarity, this recooler system is not shown in the diagram. Figure 2 It is displayed in the middle.

[0057] Temperature sensor 917 measures the temperature of the upper region of element 930 and transmits the measured temperature value to controller 912, which controls temperature control element 916 arranged at temperature control fluid line 921. Temperature control fluid line 921 is also supplied by temperature control fluid storage container 920 and includes temperature control fluid inlet 914 and temperature control fluid outlet 918. In an embodiment not shown here, each of the two temperature control loops has a dedicated temperature control fluid storage container.

[0058] Figure 3A schematic diagram of an EUV projection lens 340 with parallel connections according to the present invention is shown. To reduce heat-induced drift and wavefront aberration, the present invention addresses five problems described in the prior art through multiple different temperature control and shielding systems (see explanation with reference to Figure 1). The heat flow Q3 in the direction of sensor frame 372 and the heat flow Q4 in the direction of reflector 392 are depicted only by way of example. Reflectors 391, 392, 393, and 394 are fixed to active mechanical bearing 395. A temperature control fluid line 302 passes through force frame 382. Temperature sensor 804 measures the temperature in force frame 382. Temperature control element 704 controls the temperature of the temperature control fluid until a target temperature value for force frame 382 is reached. For overall clarity, Figure 3 The required controls for this purpose are not shown in the table. For information on closed-loop control, refer to [reference needed]. Figure 2 The diagram shows a temperature-controlled fluid line 306 passing through a cooler and heat shield 398. The cooler and heat shield 398 heat-shields a sensor frame 372. A temperature-controlled fluid line 304 passes through a mirror support frame 397. A temperature-controlled fluid line 308 passes through the sensor frame 372 and is supplied by its own fluid storage container 516. A mirror 393 is passed through its own temperature-controlled fluid line 310, which is supplied by its own fluid storage container 519. Each element includes at least one temperature sensor 804. A common fluid storage container 515 is allocated to all the aforementioned temperature-controlled fluid lines 302, 304, and 306. (From the structurally supported mask 120...) Figure 3 EUV light 502 (not shown) is reflected at the mirror and exits the lens as EUV light 504 in the direction of wafer 124. Figure 3 (Not shown in the image). In summary, the following points should be noted:

[0059] The thermal stability of the force frame 382 is achieved through controlled water cooling. The latter can consist of multiple cooling loops.

[0060] Temperature control around the reflector is achieved through water cooling of the reflector support frames 390, 396, 397, and 399.

[0061] The optical surfaces of the beam path and mirrors are housed by a single or multiple actively cooled cooling shroud 398, thereby suppressing stray light and heat conduction from the beam path to the sensor frame 372. For clarity, this is... Figure 3 Not depicted. The heat output from the force frame 382 to the sensor frame 372 is shielded by an active or passive cooling shroud (CS) 398.

[0062] - The thermal control sensor frame 372 is achieved through active controlled water cooling of the sensor frame 372.

[0063] Design measures for suppressing thermal ventilation in the sensor frame 372 can be categorized as follows based on their effects over time:

[0064] Interferences with a time constant exceeding one hour can be suppressed through thermal control of the sensor frame and / or force frame.

[0065] Interference with sensor frames with a time constant of less than one hour can be suppressed by shielding the sensor frame with the help of a cooling or passive cooling shroud between the force frame and the sensor frame.

[0066] Cooling the sensor frame with water is very slow, meaning it has a long time constant. This means that interference can be compensated for over a long wavelength. An internal cooler suppresses high-frequency interference; the heat output would then act on the sensor frame without an internal cooler.

[0067] Furthermore, different control tasks within the EUV projection lens, such as absolute temperature stability in the case of the mirror support frame and / or drift stability in the case of the cooling shroud (force frame, mirror, sensor frame), can follow largely independent control loops. This allows for reduction of thermally induced drift and wavefront aberrations.

[0068] Figure 4 A schematic diagram of an EUV projection lens with series connection according to the present invention is shown. A single temperature-controlled fluid storage container 1020 supplies a single temperature-controlled fluid line 1007. A temperature control element 1006 is arranged on the temperature-controlled fluid line 1007 downstream of the temperature-controlled fluid inlet 1004. The three elements connected in series are linked in an exemplary manner. In this example, the fluid initially flows through a cooler and temperature shroud 1010, also referred to as an internal cooler. The fluid then flows through a force frame 1012. Finally, the fluid flows through a mirror support frame 1014. The internal cooler 1010 is temperature-controlled first because it is arranged closest to the most heat-sensitive sensor frame. The element with the highest heat load, the mirror support frame 1014—due to mirror preheating and actuator waste heat—is located at the end to avoid dragging heat output throughout the system via the temperature-controlled fluid. The force frame 1012 is positioned therebetween.

[0069] Figure 6A schematic diagram of a DUV projection lens according to the present invention is shown. Two independent temperature-controlled fluid lines 476 and 486 pass through the cooler and sensor housing 451. The upper temperature-controlled fluid line 476 is supplied by a temperature-controlled fluid storage container 470. The lower temperature-controlled fluid line 486 is supplied by a temperature-controlled fluid storage container 480. Thus, the two areas of the cooler and sensor housing 451 can be temperature-controlled independently of each other. Each of these two areas has a temperature sensor 806 and a temperature control element 706. The upper temperature-controlled fluid line 476 has an inlet 474 and an outlet 478. The lower temperature-controlled fluid line 486 has an inlet 484 and an outlet 488. For clarity, in Figure 6 The document does not describe the control of the temperature in the two zones.

[0070] Figure 7 The EUV lithography apparatus 100 shown includes a beam shaping and illumination system 102 and a projection system 104. For example... Figure 7 As shown, the beam shaping and illumination system 102 and the projection system 104 are each housed within a vacuum enclosure, wherein each vacuum enclosure is evacuated by means of an evacuation device (not shown). The vacuum enclosure is surrounded by a mechanical chamber (not shown), which provides drive devices for mechanical movement or setting optical elements. Furthermore, electrical controllers and the like may also be housed within the mechanical chamber.

[0071] EUV lithography apparatus 100 includes an EUV light source 106. A plasma source (or synchrotron) emitting EUV-range radiation 108 can be provided, for example, as the EUV light source 106, where the wavelength range of the radiation 108 is between 5 nm and 20 nm. In beam shaping and illumination system 102, the EUV radiation 108 is focused, and the desired operating wavelength is filtered out from the EUV radiation 108. The EUV radiation 108 generated by the EUV light source 106 has relatively low transmittance in air, therefore the beam guiding space in beam shaping and illumination system 102 and projection system 104 is evacuated.

[0072] Figure 7 The beam shaping and illumination system 102 shown has five mirrors 110, 112, 114, 116, and 118. After passing through the beam shaping and illumination system 102, EUV radiation 108 is guided onto a photomask (mask master) 120. The photomask 120 is also in the form of a reflective optical element and can be arranged outside the systems 102 and 104. Furthermore, EUV radiation 108 can be guided onto the photomask 120 via mirror 122. The photomask 120 has a structure that projects onto a wafer 124 or the like in a reduced manner via a projection system 104.

[0073] The projection system 104 (also referred to as the projection lens) has six mirrors M1-M6 for imaging the photomask 120 onto the wafer 124. It should be noted that the number of mirrors in the EUV lithography apparatus 100 is not limited to the number shown. More or fewer mirrors may also be provided. A force frame 380 and a sensor frame 370 are shown schematically; the force frame 380 essentially carries the mirrors of the projection lens, and the sensor frame 370 essentially serves as a reference for the position of the mirrors of the projection lens. Furthermore, the front side of the mirrors is typically curved for beam shaping.

[0074] Figure 8 A schematic diagram of a microlithography projection exposure apparatus for the DUV range 400 according to the present invention is shown. The DUV projection exposure apparatus 400 includes a beam shaping and illumination device 402 and a projection lens 404. In this case, DUV stands for "deep ultraviolet" and indicates that the wavelength of the working light is between 30 and 250 nm.

[0075] The DUV projection exposure apparatus 400 includes a DUV light source 406. For example, an ArF excimer laser that emits radiation 408 in the DUV range, for example, 193 nm, can be provided as the DUV light source 406.

[0076] Figure 8 The beam shaping and illumination device 402 shown guides DUV radiation 408 onto the photomask 420. The photomask 420 is formed as a transmissive optical element and can be arranged outside the beam shaping and illumination device 402 and the projection lens 404. The photomask 420 has a structure that projects a reduced image onto a wafer 424 or the like through the projection lens 404.

[0077] The projection lens 404 has multiple lens elements 428, 440 and / or mirrors 430 for projecting the image of the photomask 420 onto the wafer 424. In this case, the individual lens elements 428, 440 and / or mirrors 430 of the projection lens 404 can be arranged symmetrically about the optical axis 426 of the projection lens 404. It should be noted that the number of lens elements and mirrors in the DUV projection exposure apparatus 400 is not limited to the number shown. More or fewer lens elements and / or mirrors may also be provided. Furthermore, the mirrors are typically bent on their front side for beam shaping.

[0078] The air gap between the last lens element 440 and the wafer 424 can be replaced by a liquid medium 432 with a refractive index > 1. The liquid medium 432 can be, for example, high-purity water. This structure is also called immersion lithography and has increased lithographic resolution.

[0079] Although the invention has been described based on specific embodiments, many variations and alternative embodiments will be apparent to those skilled in the art, such as through combinations and / or exchanges of features of the various embodiments. Therefore, it will be apparent to those skilled in the art that these variations and alternative embodiments are also included in the invention, and that the scope of the invention is limited only to the appended claims and their equivalents.

[0080] The following terms are used as synonyms:

[0081] EUV systems and EUV projection exposure apparatuses are used synonymously with microlithography projection exposure apparatuses used in the EUV range. DUV systems and DUV projection exposure apparatuses are used synonymously with microlithography projection exposure apparatuses used in the DUV range. When cooling is used, temperature control should also be included, i.e., cooling and / or heating. Therefore, fluid, temperature control fluid, and cooling fluid are used synonymously. Furthermore, cooling hoods and coolers, as well as temperature hoods, are used synonymously. Photomasks and mask masters are used synonymously. Wafers and substrates coated with photosensitive layers (photoresist) are used synonymously. Sensor frames are abbreviated as SFr. Force frames are abbreviated as FFr. Mirror support frames are abbreviated as MSF.

[0082] Reference Symbol List

[0083] 100 Projection exposure apparatus for EUV range (= EUV system) (microlithography)

[0084] 102 EUV (beam shaping and) lighting equipment

[0085] 104 EUV projection lens with six reflectors (M1 to M6)

[0086] 106 EUV light source

[0087] 108 EUV radiation

[0088] Reflectors of EUV lighting equipment 102 (110, 112, 114, 116, 118)

[0089] 120mm optical mask, mask master (reflective)

[0090] 122 reflector

[0091] 124 wafer (=a ​​substrate coated with a photosensitive layer (photoresist))

[0092] Temperature control fluid lines 302, 304, 306, 308, 310

[0093] 340 EUV projection lens with four reflectors (391, 392, 393, 394).

[0094] 370, 371, 372 Sensor Frames (SFr)

[0095] 380, 381, 382 Force Frames (FFr)

[0096] 390° Mirror Support Frame (MSF)

[0097] 395 Active Mechanical Bearing

[0098] 396 Mirror Support Frame (MSF)

[0099] 397 Mirror Support Frame (MSF)

[0100] 398 Cooler and Heat Shield (CS)

[0101] 399 Mirror Support Frame (MSF)

[0102] 400 Projection Exposure Apparatus for DUV Range (=DUV System) (Microlithography)

[0103] 402 DUV (beam shaping and) lighting equipment

[0104] 404 DUV projection lens

[0105] 406 DUV light source

[0106] 408 DUV projection lens, DUV light at the 404 entrance

[0107] 420 optical mask, mask master (transmissive)

[0108] 424 chip

[0109] 426 projection lens, 404 optical axis

[0110] 428 lens element

[0111] 430 reflector

[0112] 432 Liquid Medium

[0113] 440 The final lens element

[0114] 450 DUV cooler and heat shield (existing technology)

[0115] 451 DUV Cooler and Heat Shield

[0116] 452 Temperature Control Fluid Line

[0117] 454 Temperature Control Fluid Inlet

[0118] 456 Temperature Control Fluid Outlet

[0119] 458 to chip DUV light

[0120] 460°C Temperature Controlled Fluid Storage Container

[0121] 470 Temperature-Controlled Fluid Storage Container

[0122] 474 Temperature Control Fluid Inlet

[0123] 476 Temperature Control Fluid Line

[0124] 478 Temperature Control Fluid Outlet

[0125] 480 Temperature Control Fluid Storage Container

[0126] 484 Temperature Control Fluid Inlet

[0127] 486 Temperature Control Fluid Line

[0128] 488 Temperature Control Fluid Outlet

[0129] 502 EUV light from structural support mask 321

[0130] EUV light in the direction of 124 on 504 wafer

[0131] 507 Force Frame Temperature Control Inlet

[0132] 508 Surface Temperature Control Inlet

[0133] 509 sensor frame temperature control inlet

[0134] 510 sensor frame temperature control outlet

[0135] 511 Surface Temperature Control Outlet

[0136] 512 Reflector Support Frame Temperature Control Inlet

[0137] 513 Reflector Support Frame Temperature Control Outlet

[0138] 514 Force Frame Temperature Control Outlet

[0139] 515FFr / MSF / CS fluid storage container

[0140] 516 SFr fluid storage container

[0141] 517 Reflector Temperature Control Inlet

[0142] 518 Reflector Temperature Control Outlet

[0143] Liquid storage container for 519 reflector

[0144] 525 Position Measurement

[0145] 602 Temperature Control Fluid Line

[0146] 607 Force Frame Temperature Control Inlet

[0147] 614 Force Frame Temperature Control Outlet

[0148] 615 Force Frame Fluid Storage Container

[0149] 625 Position Measurement

[0150] 640 EUV projection lens with four reflectors (691, 692, 693, 694).

[0151] 695 Active Mechanical Bearing

[0152] Heat flow in the direction of sensor frame 371 Q1

[0153] Heat flow of Q2 in the direction of mirror 692

[0154] Heat flow in the direction of sensor frame 372 in Q3

[0155] Heat flow in the direction of mirror 392 of Q4

[0156] Q5 user heat flow (DUV)

[0157] Q6 Heat flow from DUV projection lens 404

[0158] 702 Temperature Control Element

[0159] 704 temperature control element

[0160] 706 temperature control element

[0161] 802 Temperature Sensor (EUV, Prior Art)

[0162] 804 Temperature Sensor (EUV)

[0163] 806 Temperature Sensor (DUV)

[0164] 900 parallel connection

[0165] 902 controller

[0166] 904 Temperature Control Fluid Inlet

[0167] 906 temperature control element

[0168] 907 Temperature Sensor

[0169] 908 Temperature Control Fluid Outlet

[0170] 912 controller

[0171] 914 Temperature Control Fluid Inlet

[0172] 916 temperature control element

[0173] 917 Temperature Sensor

[0174] 918 Temperature Control Fluid Outlet

[0175] 919 Temperature Control Fluid Line

[0176] 920 Temperature Controlled Fluid Storage Container

[0177] 921 Temperature Control Fluid Line

[0178] 930 components (SFr, FFR, MSF)

[0179] 1000 series connection

[0180] 1004 Temperature Control Fluid Inlet

[0181] 1006 temperature control element

[0182] 1007 Temperature Control Fluid Line

[0183] 1008 Temperature Control Fluid Outlet

[0184] 1010 Component 1, such as coolers and heat shields

[0185] 1012 Component 2, for example, force frame

[0186] Component 3 of 1014, such as the mirror support frame.

[0187] 1020 Temperature-Controlled Fluid Storage Container

Claims

1. A microlithography projection exposure apparatus (100; 400) for EUV or DUV range, comprising an illumination device (102; 402) and a projection lens (104, 340, 640; 404), the projection lens including a force frame (380, 382) and at least two mirrors (391, 392, 393, 394), the force frame and the at least two mirrors being at least regionally passed through by at least one temperature-controlled fluid line (302, 310, 602, 919, 921) for guiding temperature-controlled fluid to control the temperature of the force frame (380, 382) and the at least two mirrors (391, 392, 393, 394), wherein the temperature-controlled fluid line (302, 310, 602, 919, 921) is connected to at least one temperature-controlled fluid storage container (615, 515, 519, 920), and wherein at least one temperature control element (702, 704, 906, 916) for controlling the temperature of the temperature control fluid is disposed at or within the temperature control fluid line (302, 310, 602, 919, 921), wherein The force frame (380, 382) and each of the at least two reflectors (391, 392, 393, 394) are passed through each other independently by at least one separate temperature-controlled fluid line (302, 310, 602, 919, 921). in, The microlithography projection exposure apparatus (100; 400) further includes a cooler and a heat shield (398, 450, 451), which are at least regionally traversed by at least one temperature-controlled fluid line (306, 452, 476, 486, 919, 921) for guiding temperature-controlled fluid to control the temperature of the cooler and heat shield (398, 450, 451). The temperature-controlled fluid line (306, 452, 476, 486, 919, 921) is connected to at least one temperature-controlled fluid storage container (470, 480, 515, 460, 920), and at least one temperature control element (704, 706, 906, 916) for controlling the temperature of the temperature-controlled fluid is disposed on the temperature-controlled fluid line (306, 452, 476, 486, 919, 921). At locations 486, 919, 921) or within the temperature-controlled fluid lines, the cooler and heat shield (398, 450, 451) are passed through by at least one of the temperature-controlled fluid lines (306, 452, 476, 486, 919, 921) independently of each of the at least two reflectors (391, 392, 393, 394). The force frame (380, 382) is connected in series with the cooler and heat shield (398, 450, 451) and is passed through by the same temperature-controlled fluid line (306, 452, 476, 486, 919, 921).

2. The projection exposure apparatus according to claim 1, wherein, Each of the at least two reflectors (391, 392, 393, 394) is connected to a reflector support frame (390, 396, 397, 399), and each of the reflector support frames (390, 396, 397, 399) is connected to the force frame (380, 382).

3. The projection exposure apparatus according to claim 1 or 2, wherein, In each case, each temperature-controlled fluid line (302, 306, 310, 452, 476, 486, 602, 919, 921) is equipped with at least one individual temperature control element (702, 704, 706, 906, 916) such that the corresponding temperature-controlled fluid in the respective temperature-controlled fluid line (302, 306, 310, 452, 476, 486, 602, 919, 921) can be temperature-controlled on an individual basis.

4. The projection exposure apparatus according to claim 1 or 2, wherein, At least two temperature control loops are connected in parallel with each other, and each temperature control loop has at least one of the temperature control fluid lines (302, 306, 310, 452, 476, 486, 602, 919, 921).

5. The projection exposure apparatus according to claim 4, wherein, At least two of the temperature control loops are supplied via the following: -Common temperature-controlled fluid storage containers (470, 480, 615, 515, 519, 460, 920) or - In each case, at least one separate temperature-controlled fluid storage container (470, 480, 615, 515, 519, 460, 920).

6. The projection exposure apparatus according to claim 1 or 2, wherein, At least one temperature sensor (804, 806, 907, 917) is disposed at or in the force frame (380, 382) and at least two reflectors (391, 392, 393, 394) for measuring the temperature at or in the force frame (380, 382) and at least two reflectors (391, 392, 393, 394).

7. The projection exposure apparatus according to claim 6, wherein, At least one controller is provided for closed-loop control of the temperature control elements (702, 704, 706, 906, 916), based on the temperature measured by the temperature sensors (804, 806, 907, 917) at or in the force frame (380, 382) and at least two reflectors (391, 392, 393, 394).

8. The projection exposure apparatus according to claim 1 or 2, wherein, At least one cooler and heat shield (398; 451) has active temperature control and / or passive temperature control, and is arranged between at least two of the force frame (380, 382) and at least two reflectors (391, 392, 393, 394).

9. The projection exposure apparatus (100) according to claim 8, wherein, The EUV beam path and at least one reflector (391, 392, 393, 394) are housed by at least one cooler with active temperature control and a heat shield (398).

10. The projection exposure apparatus according to claim 1 or 2, wherein, The temperature-controlled fluid storage containers (470, 480, 615, 515, 519, 460, 920) and the temperature control elements (702, 704, 706, 906, 916) are arranged outside the projection lenses (104, 340, 640; 404).

11. A method for controlling the temperature of a force frame (380, 382) and at least two mirrors (391, 392, 393, 394) in a microlithography projection exposure apparatus (100; 400) provided for EUV or DUV range, said force frame and said at least two mirrors being passed through each other independently by at least one separate temperature-controlled fluid line (302, 310, 602, 919, 921), wherein at least one temperature-controlled fluid line (302, 310, 602, 919, 921) is provided for guiding temperature-controlled fluid through said force frame (380, 382) and at least two mirrors (391, 392, 393, 394), said force frame and said at least two mirrors being temperature-controlled using at least the following steps: - Define the target temperature of the at least two reflectors (391, 392, 393, 394). -Measure the actual temperature of at least two reflectors (391, 392, 393, 394) using at least one temperature sensor (804, 806, 907, 917) at or among at least two reflectors (391, 392, 393, 394). - Compare the actual temperature with the target temperature; The temperature of the temperature-controlled fluid is controlled by means of at least one temperature control element (702, 704, 906, 916) located at or within the at least one temperature-controlled fluid line (302, 310, 602, 919, 921) until the deviation between the actual temperature of the at least two reflectors (391, 392, 393, 394) and the target temperature is below a specified limit. in, The microlithography projection exposure apparatus (100; 400) further includes a cooler and a heat shield (398, 450, 451), which are at least regionally traversed by at least one temperature-controlled fluid line (306, 452, 476, 486, 919, 921) for guiding temperature-controlled fluid to control the temperature of the cooler and heat shield (398, 450, 451). The temperature-controlled fluid line (306, 452, 476, 486, 919, 921) is connected to at least one temperature-controlled fluid storage container (470, 480, 515, 460, 920), and at least one temperature control element (704, 706, 906, 916) for controlling the temperature of the temperature-controlled fluid is disposed on the temperature-controlled fluid line (306, 452, 476, 486, 919, 921). At locations 486, 919, 921) or within the temperature-controlled fluid lines, the cooler and heat shield (398, 450, 451) are passed through by at least one of the temperature-controlled fluid lines (306, 452, 476, 486, 919, 921) independently of each of the at least two reflectors (391, 392, 393, 394). The force frame (380, 382) and the cooler and heat shield (398, 450, 451) are connected in series and are passed through by the same temperature-controlled fluid line (306, 452, 476, 486, 919, 921).

12. The method according to claim 11, wherein, The temperature control is achieved through at least one closed-loop control circuit.

Images