JP2011029511A - Optical system, exposure device and method of manufacturing device - Google Patents

Abstract

An optical system, an exposure apparatus, and a device manufacturing method that suppress a temperature change of a casing due to radiant heat from the outside are provided.
A lens barrel 27 in which a mirror is supported is enclosed by a cover 35 having an outer surface 35b having a reflectance higher than that of light on the outer surface 27b of the lens barrel 27. Thereby, the radiant heat from the outside of the cover 35 is easily reflected by the outer surface 35 b of the cover 35. Further, the lens barrel 27 is surrounded by heat exchange portions 41 to 46 that are provided between the inner surface 35 a of the cover 35 and the outer surface 27 b of the lens barrel 27 and exchange heat with the lens barrel 27 by radiant heat transfer. Provided. And based on the detection signal from the temperature sensors 51-56 which detect the temperature of the lens-barrel 27, the heat exchange parts 41-46 are controlled and the temperature of the lens-barrel 27 is adjusted.
[Selection] Figure 2

Description

  The present invention relates to an optical system including a housing that supports an optical element, an exposure apparatus including the optical system, and a device manufacturing method using the exposure apparatus.

  In general, an exposure apparatus for manufacturing a microdevice such as a semiconductor integrated circuit includes an illumination optical system that illuminates exposure light on a mask such as a reticle on which a predetermined pattern is formed, and a pattern of the mask illuminated by the exposure light. A projection optical system that projects an image onto a substrate such as a wafer or a glass plate coated with a photosensitive material (see, for example, Patent Document 1). In such an exposure apparatus, a higher resolution of the projection optical system is demanded in order to achieve higher integration of the semiconductor integrated circuit and finer pattern images associated with the higher integration. For this reason, among the techniques for realizing high resolution, particularly, the shortening of the wavelength of the exposure light used in the exposure apparatus is rapidly progressing, and EUV (Extreme Ultraviolet) light or EB (Electron Beam) is used as the exposure light. As a result, an exposure apparatus to be used as an exposure apparatus has been intensively developed.

JP 2004-304145 A

  By the way, in the exposure apparatus that uses the EUV light as described above as the exposure light, the exposure light is absorbed by any substance and thus does not pass through the air. Therefore, in an exposure apparatus using EUV light, there are optical systems such as an illumination optical system and a projection optical system, and further a drive system such as a stage drive source on which a substrate is placed and a stage drive source on which a reticle is placed. And housed in one chamber forming a vacuum atmosphere. In such a configuration, even if the inside of the chamber is in a vacuum atmosphere, heat generated from each drive source is transmitted as radiant heat to the housing of the illumination optical system and the projection optical system. As a result, the housing may be thermally deformed due to the accumulation of heat transferred in this way. Since the illumination optical system and the projection optical system include a plurality of optical elements, and the plurality of optical elements are supported by the casing, the positions of the various optical elements supported by the casing are affected by this thermal deformation. There was a changing problem.

  The present invention has been made in view of the above circumstances, and an object of the present invention is to provide an optical system, an exposure apparatus, and a device manufacturing method that suppress a change in the temperature of the housing due to external radiant heat.

In order to solve the above-described problems, the present invention employs the following configuration corresponding to FIGS. 1 and 2 shown in the embodiment.
The present invention includes a housing (27) that supports the optical elements (24, 28 to 33), and an outer surface (35b) having a higher reflectance than the light reflectance of the outer surface (27b) of the housing (27). ) And a cover (35) including the casing (27);
A temperature adjustment mechanism (41 to 46) provided between the inner surface (35a) of the cover (35) and the outer surface (27b) of the casing (27) to adjust the temperature of the casing (27). And an optical system.

According to the above configuration, the outer surface (35b) of the cover (35) is the outer surface (27 of the housing (27)).
b) Since it has a higher reflectance than that of the optical system not having such a configuration, the space between the cover (35) and the housing (27), and further the outer surface of the housing (27) In contrast to (27b), radiant heat from outside the cover (35) is difficult to propagate. In addition, since the temperature of the housing (27) is adjusted in the space between the cover (35) and the housing (27), that is, the space in which the propagation of radiant heat from the outside is suppressed, the radiant heat from the outside is reduced. Compared with a configuration in which the temperature is adjusted in the propagation space, the temperature adjustment accuracy can be improved, and the load related to the temperature adjustment can be reduced. Thereby, it becomes possible to suppress that the housing | casing (27) is thermally deformed by the temperature change of the housing | casing (27) by the radiant heat from the outside.

  In addition, in order to explain the present invention in an easy-to-understand manner, the description has been made in association with the reference numerals of the drawings shown in the embodiments.

  ADVANTAGE OF THE INVENTION According to this invention, it becomes possible to suppress that the said housing | casing thermally deforms by the temperature change of the housing | casing by the radiant heat from the outside.

1 is a schematic block diagram that shows an exposure apparatus in the present embodiment. The schematic block diagram which shows the inside of the cover in this embodiment. The schematic block diagram which shows the temperature control mechanism in a modification. The schematic block diagram which shows the temperature control mechanism in a modification. The flowchart of the manufacture example of a device. The detailed flowchart regarding the board | substrate process in the case of a semiconductor device.

  Hereinafter, an embodiment embodying the present invention will be described with reference to FIGS. 1 and 2. FIG. 1 is a schematic block diagram that shows an exposure apparatus in the present embodiment. In this embodiment, the Z axis is taken in parallel to the optical axis of the projection optical system 16, and the Y axis is taken along the scanning direction of the reticle R and the wafer W during scanning exposure in a plane perpendicular to the Z axis. A description will be given by taking the X axis along the non-scanning direction orthogonal to the scanning direction. The rotation directions around the X, Y, and Z axes are also referred to as the θx direction, the θy direction, and the θz direction.

  As shown in FIG. 1, the exposure apparatus 11 of the present embodiment uses extreme ultraviolet light, ie, EUV (Extreme Ultraviolet) light, which is a soft X-ray region having a wavelength of about 100 nm or less emitted from a light source device 12, as exposure light EL. EUV exposure apparatus used as Such an exposure apparatus 11 includes a chamber 13 (a portion surrounded by a two-dot chain line in FIG. 1) in which the inside is set to a vacuum atmosphere lower in pressure than the atmosphere, and a predetermined pattern is formed in the chamber 13. The formed reflective reticle R and the wafer W having a surface coated with a photosensitive material such as a resist are appropriately conveyed. Note that a laser-excited plasma light source is used as the light source device 12 of the present embodiment, and the light source device 12 emits EUV light having a wavelength of 5 to 20 nm (for example, 13.5 nm) as the exposure light EL. It is like that.

  The exposure light EL emitted from the light source device 12 disposed outside the chamber 13 enters the chamber 13. The exposure light EL that has entered the chamber 13 illuminates the reticle R held by the reticle stage 15 via the illumination optical system 14, and the exposure light EL reflected by the reticle R passes through the projection optical system 16. Then, the wafer W held on the wafer stage 17 is irradiated.

The illumination optical system 14 includes a lens barrel 18 (a portion surrounded by a one-dot chain line in FIG. 1) in which the inside is set to a vacuum atmosphere, as in the inside of the chamber 13. In the lens barrel 18, the light source device 1
2 is provided. The collimating mirror 19 for condensing the exposure light EL emitted from 2 is provided. The collimation mirror 19 converts the incident exposure light EL into substantially parallel light and emits it. Then, the exposure light EL emitted from the collimating mirror 19 enters a fly-eye optical system 20 (a part surrounded by a broken line in FIG. 1) which is a kind of optical integrator. The fly-eye optical system 20 includes a pair of fly-eye mirrors 21 and 22, and the incident-side fly-eye mirror 21 disposed on the incident side of the fly-eye mirrors 21 and 22 has an incident surface that is a reticle. It is arranged at a position optically conjugate with the R irradiated surface Ra (that is, the lower surface in FIG. 1 and the pattern forming surface). The exposure light EL reflected by the incident-side fly-eye mirror 21 is incident on the emission-side fly-eye mirror 22 arranged on the emission side.

  Further, the illumination optical system 14 is provided with a condenser mirror 23 that emits the exposure light EL emitted from the emission side fly-eye mirror 22 to the outside of the lens barrel 18. Then, the exposure light EL emitted from the condenser mirror 23 is held on the reticle stage 15 by a reflection mirror 24 for folding installed in a lens barrel 27 included in a cover 35 (see FIG. 2) described later. Guided to reticle R. A reflective layer that reflects the exposure light EL is formed on the reflective surfaces of the mirrors 19 and 21 to 24 constituting the illumination optical system 14, respectively. The reflective layer is composed of a multilayer film in which molybdenum (Mo) and silicon (Si) are alternately stacked.

  The reticle stage 15 is disposed on the object plane side of the projection optical system 16 and includes a first electrostatic chuck holding device 25 for electrostatic chucking of the reticle R. The first electrostatic chucking and holding device 25 includes a base (not shown) made of a dielectric material and having a suction surface 25a, and a plurality of electrodes (not shown) arranged in the base. When a voltage is applied to each electrode unit from a voltage application unit (not shown), the reticle R is electrostatically adsorbed on the adsorption surface 25a by the Coulomb force generated from the base.

  The reticle stage 15 includes a reticle stage driving unit (not shown) that moves the reticle R held by the first electrostatic chuck holding device 25 in a Y-axis direction (left and right direction in FIG. 1) with a predetermined stroke, and a first static stage. A support stage 26 that supports the electroadsorption holding device 25 is provided. The reticle stage drive unit is configured to be able to move the reticle R also in the X-axis direction (direction orthogonal to the paper surface in FIG. 1) and the θz direction. Note that, when the exposure light EL is illuminated on the irradiated surface Ra of the reticle R, a substantially arc-shaped illumination region extending in the X-axis direction is formed on a part of the irradiated surface Ra.

  The projection optical system 16 is an optical system that reduces the pattern image of the irradiated surface Ra of the reticle R illuminated with the exposure light EL to a predetermined reduction magnification (for example, 1/4 times). Similarly, a lens barrel 27 whose inside is set to a vacuum atmosphere is provided. A plurality of (six in this embodiment) reflective mirrors 28, 29, 30, 31, 32 and 33 are accommodated in the lens barrel 27. Each of the mirrors 28 to 33 is held by the lens barrel 27 via a mirror support device (not shown). The exposure light EL guided from the reticle R side, which is the object plane side, is in the order of the first mirror 28, the second mirror 29, the third mirror 30, the fourth mirror 31, the fifth mirror 32, and the sixth mirror 33. The light is reflected and guided to the irradiated surface Wa of the wafer W held on the wafer stage 17. A reflection layer that reflects the exposure light EL is formed on the reflection surface of each of the mirrors 28 to 33. The reflective layer is composed of a multilayer film in which molybdenum (Mo) and silicon (Si) are alternately stacked.

The wafer stage 17 is configured to move the wafer W held by the second electrostatic chuck holding device 34 for electrostatic chucking of the wafer W with a predetermined stroke in the Y-axis direction. A wafer stage drive unit that does not. The second electrostatic chucking and holding device 34 includes a base (not shown) made of a dielectric material and having a suction surface 34a, and a plurality of electrodes (not shown) arranged in the base. When a voltage is applied to each electrode unit from a voltage application unit (not shown), the wafer W is electrostatically adsorbed on the adsorption surface 34a by the Coulomb force generated from the base. The wafer stage drive unit is configured to be able to move the wafer W held by the second electrostatic chuck holding device 34 also in the X-axis direction and the Z-axis direction (vertical direction in FIG. 1). Further, the wafer stage 17 includes a wafer holder (not shown) that holds the second electrostatic chucking holding device 34 and a Z leveling (not shown) that adjusts the position of the wafer holder in the Z-axis direction and the tilt angles around the X-axis and the Y-axis. And built-in mechanism.

  When the pattern of the reticle R is exposed to one shot area on the wafer W, the reticle R is driven in the Y-axis direction by driving the reticle stage driving unit while irradiating the reticle R with the illumination area by the illumination optical system 14. The projection optical system 16 is moved with respect to the movement of the reticle R along the Y-axis direction by moving the wafer stage drive unit (for example, from the + Y direction side to the −Y direction side) for every predetermined stroke. Move at a speed ratio according to the reduction ratio. When the pattern formation on one shot area is completed, the pattern formation on the other shot areas of the wafer W is continuously performed.

  Next, the lens barrel 27 that supports the mirrors 28 to 33 in the projection optical system 16 and the cover 35 that encloses the lens barrel 27 will be described with reference to FIG. FIG. 2 is a schematic configuration diagram showing the inside of the cover, in which the cover 35 is shown in cross section and the lens barrel 27 is shown in side view.

  As shown in FIG. 2, the cover 35 includes a lens barrel 27. A vacuum atmosphere is formed between the inner surface 35 a of the cover 35 and the outer surface 27 b of the lens barrel 27 as in the case of the lens barrel 27. The lens barrel 27 has a hollow, substantially cylindrical shape made of a material having a low coefficient of thermal expansion (in this embodiment, Super Invar), and each of the above-described components is provided via a mirror support device (not shown) provided therein. The mirrors 24 and 28 to 33 are held. The lens barrel 27 is provided with through holes (not shown) at appropriate positions in the portion corresponding to the optical path of the exposure light EL so that the progression of the exposure light EL emitted from the illumination optical system 14 is not hindered. ing. A flange portion 37 for supporting the lens barrel 27 on a support frame 36 fixed to the main body of the exposure apparatus 11 is provided in the vicinity of the approximate center in the longitudinal direction of the lens barrel 27. The lens barrel 27 is supported by the support frame 36 via the flange portion 37.

  On the other hand, the cover 35 is constituted by a covered cylindrical upper cover 38 and a bottomed cylindrical lower cover 39 made of metal such as SUS. Similar to the lens barrel 27, these upper cover 38 and lower cover 39 are portions corresponding to the optical path of the exposure light EL so that the progression of the exposure light EL emitted from the illumination optical system 14 is not hindered. A through hole (not shown) is provided at an appropriate position. Further, the upper cover 38 and the lower cover 39 are made of the lens barrel 27 via a cover heat insulating material 40 made of, for example, synthetic resin having a lower thermal conductivity than the cover 35 such as PTFE (polytetrafluoroethylene). The flange portion 37 is connected and fixed to the flange portion 37 so as to sandwich the flange portion 37. If such a heat insulating material for cover 40 is provided, since heat conduction through the flange portion 37 is suppressed between the cover 35 and the lens barrel 27, even if a temperature change occurs in the cover 35. The temperature change in the lens barrel 27 is suppressed.

Further, the outer surface 35 b of the cover 35 has a mirror finish, and has a reflectance higher than the reflectance of light on the outer surface 27 b of the lens barrel 27. With such a configuration, the radiant heat from the outside (outside) of the cover 35 is easily reflected by the outer surface 35b of the cover 35, the temperature change of the cover 35 itself due to the radiant heat from the outside is suppressed, and the radiant heat is reduced. Propagation to the lens barrel 27 is also suppressed. Therefore, the lens barrel 27 included in the cover 35 is less susceptible to temperature change due to external radiant heat than the lens barrel configured not to be included in the cover 35, and the thermal deformation thereof is suppressed. .

  On the other hand, on the inner surface 35 a of the cover 35, the heat exchange portions 41, 42, 43, 44, 45, 46 inhibit the progression of the exposure light EL emitted from the illumination optical system 14 so as to surround the lens barrel 27. It is provided in a position where there is nothing. These heat exchanging units 41 to 46 adjust the temperature of the lens barrel 27 by exchanging heat with the lens barrel 27 using radiant heat transfer. In the present embodiment, the heat exchanging unit 41 includes a radiation temperature adjusting plate 41A that receives radiant heat from the lens barrel 27, and a temperature control unit 41B that controls the temperature of the radiation temperature adjusting plate 41A. The radiation temperature control plate 41A is disposed at a position spaced apart from the outer surface 27b of the lens barrel 27 by a predetermined distance. The temperature control unit 41B includes, for example, a Peltier element that adjusts the temperature of the radiation temperature control plate 41A, and a heat exchange mechanism that exchanges heat with the Peltier element using heat conduction. The other heat exchanging units 42 to 46 are different in arrangement position from the heat exchanging unit 41 and have the same configuration as the heat exchanging unit 41 in other configurations. Therefore, the detailed description is abbreviate | omitted by attaching | subjecting the same code | symbol. Moreover, the temperature sensor 51 which detects the temperature of the lens-barrel 27 in the position which is the outer surface 27b of the lens-barrel 27, and opposes the radiation temperature control boards 41A-46A of each heat exchange part 41-46. 52, 53, 54, 55, and 56 are provided, respectively.

  The main control unit 50 that performs overall control of various control units such as a control unit that controls the driving amount of the reticle stage 15 and a control unit that controls the driving amount of the wafer stage 17 includes the heat exchange unit 41, the temperature sensor 51, and the like. Is connected. The other temperature control units 42B to 46B and the other temperature sensors 52 to 56 are also connected to the main control unit 50. However, for convenience of explanation, the electrical connection between them is omitted in FIG. To do. And when the detection signal which shows the temperature which each temperature sensor 51-56 detected is input into the main control part 50, in the main control part 50, the temperature of the site | part to which each temperature sensor 51-56 was attached becomes target value. As much as possible, control signals are output to the heat exchanging units 41 to 46 facing the temperature sensors 51 to 56 to control the temperatures of the radiation temperature control plates 41A to 46A, respectively.

  For example, a target value of the temperature of the lens barrel 27 is stored in the storage unit included in the main control unit 50. In addition, the storage unit stores various parameters for calculating control values for the heat exchange units 41 to 46 as control targets based on detection values of the temperature sensors 51 to 56 and target values corresponding thereto. Has been. And when the detected value from each temperature sensor 51-56 is input into the main control part 50, the main control part 50 will be the target value and detected value of each temperature sensor 51-56 for every control period of temperature control. Various control processes such as a proportional / integral process (PI process) or a proportional / integral / differential process (PID process) are performed on the deviation, and a control signal for setting the temperature of the part in the lens barrel 27 to a target value is generated. Based on the processing result of the arithmetic processing, the heat is output to the heat exchange units 41 to 46 corresponding to the temperature sensors 51 to 56.

  If it is such a structure, since each heat exchange part 41-46 will be controlled so that the radiation temperature control boards 41A-46A may become the optimal temperature according to the temperature of the lens-barrel 27 at that time, a radiation temperature control board It becomes possible to hold the temperature of the lens barrel 27 whose temperature is controlled by 41A to 46A with a target value with high accuracy. In addition, since a plurality of such heat exchanging portions 41 to 46 are provided so as to surround the lens barrel 27, temperature adjustment is performed on a plurality of locations of the lens barrel 27, that is, the entire lens barrel 27. As a result, a temperature gradient in the lens barrel 27 is less likely to occur, and the temperature of the lens barrel 27 can be adjusted more efficiently.

It should be noted that the wires and pipes connected to the temperature sensors 51 to 56 and the heat exchanging parts 41 to 46 are drawn out to the outside of the cover 35 through communication holes (not shown) provided in the flange part 37 of the lens barrel 27. In this way, if the wiring connected to the heat exchange parts 41 to 46 is drawn out of the cover 35 through the flange part 37 provided on the lens barrel 27, the cover 35 subjected to mirror finishing is connected to the wiring. There is no need for through-holes to pass through. When a through hole is formed in the cover 35, there is a possibility that radiant heat from the outside may propagate to the lens barrel 27 through the through hole. However, with the above-described configuration, radiant heat from the outside propagates to the lens barrel 27. It is also possible to further suppress this by the amount that the through holes formed in the cover 35 are reduced.

  Then, the projection optical system 16 having such a cover 35 is embodied in the exposure apparatus 11, so that the outside of the lens barrel 27, for example, the inner wall of the chamber 13, the drive unit of the reticle stage 15 and the wafer stage 17, and the illumination optical system 14. The radiant heat from the lens barrel 18 and the like is easily reflected by the cover 35, and the radiant heat can be prevented from propagating to the lens barrel 27.

As described above, according to the projection optical system 16 in the present embodiment, the following effects can be obtained.
(1) According to the above embodiment, the cover 35 that encloses the lens barrel 27 is provided in the chamber 13, and the outer surface 35 b of the cover 35 is higher than the light reflectance at the outer surface 27 b of the lens barrel 27. Has reflectivity. Thereby, the radiant heat from the outside of the cover 35 is easily reflected by the outer surface 35 b of the cover 35, and the radiant heat can be prevented from propagating to the lens barrel 27. Therefore, in the lens barrel 27 included in the cover 35, a temperature change due to external radiant heat is less likely to occur and the thermal deformation is suppressed compared to a lens barrel configured not included in the cover 35. . As a result, the positional deviations of the mirrors 28 to 33 mounted on the lens barrel 27 are suppressed, and the accuracy of the pattern image formed on the wafer W by the exposure apparatus 11 can be improved.

  (2) The temperature of the lens barrel 27 is adjusted in the space between the cover 35 and the lens barrel 27, that is, the space in which the propagation of radiant heat from the outside is suppressed by the cover 35. For this reason, compared to a configuration in which temperature adjustment is performed in a space in which radiant heat from the outside propagates, not only can the temperature adjustment accuracy of the lens barrel 27 be improved, but also the load associated with temperature adjustment is reduced. It is also possible to do.

  (3) According to the above embodiment, based on the detection signals of the temperature sensors 51 to 56 that detect the temperature of the lens barrel 27, the heat exchange units 41 are set so that the radiation temperature adjusting plates 41A to 46A have an optimum temperature. ~ 46 are controlled. As a result, the temperature of the lens barrel 27 can be accurately maintained at the target value.

  (4) According to the above embodiment, since a plurality of the heat exchanging parts 41 to 46 are provided so as to surround the lens barrel 27, it is possible to adjust the temperature for the entire lens barrel 27. As a result, a temperature gradient in the lens barrel 27 is less likely to occur, and the temperature of the lens barrel 27 can be adjusted efficiently.

  (5) According to the above embodiment, the upper cover 38 and the lower cover 39 constituting the cover 35 are connected and fixed to the flange portion 37 of the lens barrel 27 via the cover heat insulating material 40. By doing so, heat conduction through the flange portion 37 between the cover 35 and the lens barrel 27 is suppressed, and even if a temperature change occurs in the cover 35, the temperature change in the lens barrel 27 can be suppressed. Is possible.

  (6) According to the above-described embodiment, wiring, piping, and the like connected to each component in the cover 35 are pulled out to the outside of the cover 35 through a communication hole (not shown) provided in the flange portion 37 of the lens barrel 27. . Thereby, it is possible to reduce the number of through holes formed in the cover 35, and it is possible to further suppress the propagation of radiant heat from the outside to the lens barrel 27 by the amount of the reduced through holes.

In addition, you may change the said embodiment as follows.
In the above embodiment, the upper cover 38 and the lower cover 39 are interposed via the cover heat insulating material 40 in order to suppress heat conduction between the upper cover 38 and the lower cover 39 constituting the cover 35 and the lens barrel 27. The flange portion 37 is connected and fixed. For example, when the heat conduction from the cover 35 to the flange portion 37 is within a predetermined design range, the upper cover 38 and the lower cover 39 are directly connected to the flange portion 37 to cover the cover. The heat insulating material 40 may be omitted. With such a configuration, the number of members required for the exposure apparatus 11 can naturally be reduced, and the connection structure between the cover 35 and the flange portion 37 itself can be simplified. The convenience can be improved.

  In the above embodiment, the heat exchanging portions 41 to 46 are provided on the inner surface 35 a of the cover 35 so that the heat exchanging portions 41 to 46 are separated from the outer surface 27 b of the lens barrel 27 by a predetermined distance. The temperature of the lens barrel 27 is adjusted using radiant heat transfer between the heat exchangers 41 to 46. The position of the temperature adjustment mechanism is not limited to this, and may be between the outer surface 27b of the lens barrel 27 and the inner surface 35a of the cover 35. For example, the temperature adjusting mechanism may be disposed on the outer surface 27b of the lens barrel 27. If the temperature adjusting mechanism is in contact with the outer surface 27b of the lens barrel 27 as described above, the temperature of the lens barrel 27 can be adjusted using solid heat conduction in the lens barrel 27 and the temperature adjusting mechanism. Therefore, local temperature adjustment in the lens barrel 27 can be performed in accordance with the size of the temperature adjustment mechanism, and any combination of the solid heat conduction and the radiant heat transfer described in the above embodiment can be used. The controllability related to the temperature adjustment of the lens barrel 27 can be expanded.

  In the above embodiment, the configuration in which the heat exchange portions 41 to 46 are directly provided on the inner surface 35a of the cover 35 has been described. However, a heat insulating material is provided between the inner surface 35a of the cover 35 and the heat exchange portions 41 to 46. May be. As this heat insulating material, a heat insulating material made of, for example, a synthetic resin having a lower thermal conductivity than the cover 35, such as PTFE (polytetrafluoroethylene), can be used as in the case of the heat insulating material for cover 40.

  In addition to the heat exchanging portion 41 of the above embodiment, as shown in FIG. 3, the heat shielding member 57 is erected on the inner surface 35 a of the cover 35 so as to surround the heat exchanging portion 41. May be. With such a configuration, on the outer surface 27b of the lens barrel 27, the range in which heat exchange with the heat exchange unit 41 is possible is limited by the heat shield member 57, while the amount of heat that the heat exchange unit 41 can exchange heat with. Since it does not change depending on the presence or absence of the heat shield member 57, it is possible to improve the efficiency of heat exchange in the limited range. Therefore, for example, when a specific location where the temperature changes particularly on the outer surface 27b of the lens barrel 27 is known in advance, efficient heat exchange between the range including the specific location and the heat exchange unit 41 is possible. It becomes possible to do. Therefore, even when the temperature control region on the outer surface 27b of the lens barrel 27 is spatially significantly different in the outer surface 27b, the combination of the heat exchanging part and the heat shield member 57 allows the control region. The temperature can be adjusted to match The heat shield member 57 may be a heat shield member having a mirror-finished surface, or a heat shield member having a film having a high radiant heat reflectivity formed on the surface.

  In the above embodiment, the heat exchange parts 41 to 46 are fixed to the inner surface 35a of the cover 35, and the distance between the outer surface 27b of the lens barrel 27 and the heat exchange parts 41 to 46 is fixed to a predetermined value. Yes. Not limited to this, as shown in FIG. 4, the heat exchanging portion 41 or the heat shielding member 57 is mounted, and the heat exchanging portion 41 or the heat shielding member 57 can move toward and away from the outer surface 27 b of the lens barrel 27. The structure in which the member 58 is provided on the cover 35, that is, the distance between the outer surface 27b of the lens barrel 27 and each heat exchanging portion 41 to 46, or the distance between the outer surface 27b of the lens barrel 27 and each heat shielding member 57 is changed. It may be a configuration. Further, a movement control unit 59 for moving the moving member 58 is connected to the main control unit 50, and the movement control unit 59 is connected to the outside of the lens barrel 27 in accordance with a control signal input from the main control unit 50 to the movement control unit 59. The structure which changes the distance of the surface 27b and each heat exchange part 41-46 or the distance of the outer surface 27b of the lens-barrel 27 and the heat insulation member 57 based on the detected value of a temperature sensor may be sufficient.

  According to such a configuration, the temperature of the outer surface 27b of the lens barrel 27 is not only the amount of radiation from each heat exchanging portion 41 to 46, but also the distance between the outer surface 27b of the lens barrel 27 and each heat exchanging portion 41 to 46. Control is also possible. Further, the temperature control range on the outer surface 27 b of the lens barrel 27 can be controlled not only by the size of the heat shield member 57 but also by the distance between the outer surface 27 b of the lens barrel 27 and each heat shield member 57. For example, if the radiation temperature adjustment plate 41A approaches the lens barrel 27, the amount of radiation from the radiation temperature adjustment plate 41A increases on the outer surface 27b of the lens barrel 27, and the heat shield member 57 approaches the lens barrel 27. Then, the temperature control range on the outer surface 27b of the lens barrel 27 becomes more local. By doing so, the temperature control range on the outer surface 27b of the lens barrel 27 is also greatly improved. In addition, the structure which provides the heat exchange part 41 and the heat-insulation member 57 in a different moving member, and each moves independently may be sufficient. With such a configuration, the degree of freedom in adjusting the temperature of the lens barrel 27 is further improved.

  In the above embodiment, by providing the heat exchanging portions 41 to 46 so as to surround the lens barrel 27, temperature adjustment for a plurality of locations (the entire lens barrel 27) on the outer surface 27 b of the lens barrel 27 is performed. . For example, when the temperature of the lens barrel 27 is adjusted, the specific location where the temperature rises on the outer surface 27b of the lens barrel 27 is grasped in advance. An embodiment in which only the heat exchange unit is provided may be used.

  -The main control part 50 of the said embodiment controls each heat exchange part 41-46 so that the temperature of the lens-barrel 27 may become a target value based on the detection signal of the temperature sensors 51-56. Not only this but the structure which omitted the temperature sensor may be sufficient when adjusting the temperature of the lens-barrel 27 using the heat exchange parts 41-46. In such a case, for example, it is possible to adjust the temperature of the lens barrel 27 by controlling the radiation temperature adjusting plates 41A to 46A of the respective heat exchanging units 41 to 46 so as to always have the same temperature.

  In the above embodiment, the flange portion 37 is provided on the lens barrel 27, and the flange portion 37 is supported on the support frame 36 of the exposure apparatus 11. However, the present invention is not limited to this, and for supporting the lens barrel 27 on the support frame 36, for example, a cover supported by the support frame 36 may support the lens barrel 27.

  In the above embodiment, the outer surface 35b of the cover 35 is configured to have a mirror finish. However, the present invention is not limited to this. For reflecting radiant heat from the outside on the outer surface of the cover 35, a film having a higher radiant heat reflectivity than the outer surface 27b of the lens barrel 27 is formed on the outer surface of the cover. May be. Even if it is such a structure, the effect equivalent to the said embodiment can be acquired.

In the above embodiment, the cover 35 is provided on the lens barrel 27 of the projection optical system 16. However, the cover may be provided on the lens barrel 18 of the illumination optical system 14 without being limited thereto.
The light source device 12 of the above embodiment includes, for example, g-line (436 nm), i-line (365 nm), KrF excimer laser (248 nm), F ₂ laser (157 nm), Kr ₂ laser (146 nm), Ar ₂ laser (126 nm) The light source which can supply etc. may be sufficient. The light source device 12 amplifies the infrared or visible single wavelength laser light oscillated from the DFB semiconductor laser or fiber laser, for example, with a fiber amplifier doped with erbium (or both erbium and ytterbium). Alternatively, a light source capable of supplying harmonics converted into ultraviolet light using a nonlinear optical crystal may be used.

In the above embodiment, a discharge-type plasma light source may be used as the light source device 12 that can output EUV light.
In the above embodiment, the exposure apparatus 11 may be an exposure apparatus that uses EB (Electron Beam) as the exposure light EL.

In the above embodiment, the exposure apparatus 11 may be embodied as a step-and-repeat apparatus.
Next, an embodiment of a microdevice manufacturing method using the device manufacturing method by the exposure apparatus 11 of the embodiment of the present invention in the lithography process will be described. FIG. 5 is a flowchart showing a manufacturing example of a micro device (a semiconductor chip such as an IC or LSI, a liquid crystal panel, a CCD, a thin film magnetic head, a micro machine, etc.).

  First, in step S101 (design step), function / performance design (for example, circuit design of a semiconductor device) of a micro device is performed, and pattern design for realizing the function is performed. Subsequently, in step S102 (mask manufacturing step), a mask (reticle R or the like) on which the designed circuit pattern is formed is manufactured. On the other hand, in step S103 (substrate manufacturing step), a substrate (a wafer W when a silicon material is used) is manufactured using a material such as silicon, glass, or ceramics.

  Next, in step S104 (substrate processing step), using the mask and substrate prepared in steps S101 to S104, an actual circuit or the like is formed on the substrate by lithography or the like, as will be described later. Next, in step S105 (device assembly step), device assembly is performed using the substrate processed in step S104. Step S105 includes processes such as a dicing process, a bonding process, and a packaging process (chip encapsulation) as necessary. Finally, in step S106 (inspection step), inspections such as an operation confirmation test and a durability test of the microdevice manufactured in step S105 are performed. After these steps, the microdevice is completed and shipped.

FIG. 6 is a diagram illustrating an example of a detailed process of step S104 in the case of a semiconductor device.
In step S111 (oxidation step), the surface of the substrate is oxidized. In step S112 (CVD step), an insulating film is formed on the substrate surface. In step S113 (electrode formation step), an electrode is formed on the substrate by vapor deposition. In step S114 (ion implantation step), ions are implanted into the substrate. Each of the above steps S111 to S114 constitutes a pretreatment process at each stage of the substrate processing, and is selected and executed according to a necessary process at each stage.

  When the above-mentioned pretreatment process is completed in each stage of the substrate process, the posttreatment process is executed as follows. In this post-processing process, first, in step S115 (resist formation step), a photosensitive material is applied to the substrate. Subsequently, in step S116 (exposure step), the circuit pattern of the mask is transferred to the substrate by the lithography system (exposure apparatus 11) described above. Next, in step S117 (development step), the substrate exposed in step S116 is developed to form a mask layer made of a circuit pattern on the surface of the substrate. Subsequently, in step S118 (etching step), the exposed member in a portion other than the portion where the resist remains is removed by etching. In step S119 (resist removal step), the photosensitive material that has become unnecessary after the etching is removed. That is, in step S118 and step S119, the surface of the substrate is processed through the mask layer. By repeatedly performing these pre-processing steps and post-processing steps, multiple circuit patterns are formed on the substrate.

The exposure apparatus 11 is a mother device for manufacturing reticles or masks used in not only microdevices such as semiconductor elements but also light exposure apparatuses, EUV exposure apparatuses, X-ray exposure apparatuses, and electron beam exposure apparatuses. An exposure apparatus that transfers a circuit pattern from a reticle to a glass substrate, a silicon wafer, or the like may be used. The exposure apparatus 11 is used for manufacturing a display including a liquid crystal display element (LCD) and the like, and is used for manufacturing an exposure apparatus that transfers a device pattern onto a glass plate, a thin film magnetic head, and the like. It may be an exposure apparatus that transfers to a wafer or the like, and an exposure apparatus that is used to manufacture an image sensor such as a CCD.

  R ... reticle, W ... wafer, EL ... exposure light, Ra ... irradiated surface, Wa ... irradiated surface, 11 ... exposure device, 12 ... light source device, 13 ... chamber, 14 ... illumination optical system, 15 ... reticle stage, DESCRIPTION OF SYMBOLS 16 ... Projection optical system, 17 ... Wafer stage, 18 ... Lens barrel, 19 ... Collimating mirror, 20 ... Fly eye optical system, 21 ... Incident side fly eye mirror, 22 ... Emission side fly eye mirror, 23 ... Condenser mirror, 24 ... Reflection mirror, 25 ... First electrostatic adsorption holding device, 25a ... Adsorption surface, 26 ... Support stage, 27 ... Lens barrel as casing, 27b ... Outer surface, 28 ... First mirror, 29 ... Second mirror , 30 ... 3rd mirror, 31 ... 4th mirror, 32 ... 5th mirror, 33 ... 6th mirror, 34 ... 2nd electrostatic adsorption holding device, 34a ... adsorption surface, 35 ... cover, 35a ... inner surface, 35b ... Outer surface 36 ... Supporting frame, 37 ... Flange, 38 ... Upper cover, 39 ... Lower cover, 40 ... Heat insulating material for cover as heat insulating member, 41, 42, 43, 44, 45, 46 ... Heat exchange as temperature adjusting mechanism 41A, 42A, 43A, 44A, 45A, 46A ... radiation temperature control plate, 41B, 42B, 43B, 44B, 45B, 46B ... temperature control unit, 50 ... main control unit, 51, 52, 53, 54, 55 , 56 ... a temperature sensor as a temperature detection part, 57 ... a heat shield member as a change part, 58 ... a moving member constituting the change part, 59 ... a movement control part constituting the change part.

Claims (7)

A housing that supports the optical element;
A cover having an outer surface with a reflectance higher than the reflectance of light on the outer surface of the housing and enclosing the housing;
An optical system comprising: a temperature adjusting mechanism that is provided between an inner surface of the cover and an outer surface of the casing and adjusts a temperature of the casing. The temperature adjustment mechanism is
A temperature detection unit for detecting the temperature of the housing;
The optical system according to claim 1, wherein the temperature of the housing is adjusted based on a detection result of the temperature detection unit. The temperature adjustment mechanism is
The optical system according to claim 1, wherein the optical system is provided corresponding to a plurality of locations on the outer surface of the housing. The temperature adjustment mechanism is
A heat exchanging unit that is provided at a predetermined interval with respect to the outer surface of the housing, and performs heat exchange with the housing by radiant heat transfer;
The optical system according to claim 1, further comprising: a changing unit that changes a range in which heat exchange is performed with the heat exchange unit on an outer surface of the housing. On the outer surface of the housing, a flange portion is provided for supporting the housing on a support frame.
The optical system according to claim 1, wherein the cover is fixed to the flange portion via a heat insulating member. An illumination optical system for directing a radiation beam to a mask on which a predetermined pattern is formed;
A projection optical system that irradiates a substrate coated with a photosensitive material with a radiation beam through the mask, and
An exposure apparatus, wherein at least one of the optical systems is the optical system according to any one of claims 1 to 5. In a device manufacturing method including a lithography process,
The device manufacturing method according to claim 6, wherein the lithography process uses the exposure apparatus according to claim 6.

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