Exposure device, determination method, article manufacturing method, and program

Abstract

To provide a technique advantageous for suppressing lowering of optical performance of a projection optical system.SOLUTION: An exposure device for exposing a substrate with light though an original plate has: a projection optical system for projecting the pattern of the original plate onto the substrate; an NA diaphragm capable of changing the number of openings of the projection optical system; a temperature-adjusting part for supplying and discharging gas to / from the internal space of the projection optical system, and thereby adjusting the temperature of the space and the temperature of an optical member arranged in the internal space; and a control part for changing the condition related to the supply and the discharge of the gas by the temperature-adjusting part, according to the change in the number of openings by the NA diaphragm.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present invention relates to an exposure apparatus, a determination method, a method for manufacturing an article, and a program.

Background Art

[0002] In a lithography process for manufacturing display devices such as televisions, smartphones, and tablet terminals, an exposure apparatus is used to transfer the pattern of a master plate (mask or reticle) onto a substrate on which a photoresist (photosensitive agent) is disposed.

[0003] In recent years, in order to improve the productivity of exposure apparatuses, the illuminance of exposure light has tended to be increased, and thus techniques for reducing changes in optical performance due to the exposure light irradiating an optical system have been proposed (see Patent Document 1). Patent Document 1 discloses an exposure apparatus including a supply unit that supplies a cooling gas to an optical element disposed near the pupil position of a projection optical system, and a control unit that controls the supply unit so that the direction of supplying the cooling gas is changed according to the temperature distribution of the optical element.

[0004] On the other hand, in order to manufacture various display devices and the like using the same apparatus, in an exposure apparatus, it is required to transfer patterns having various dimensions from a very fine pattern of about 1 μm to a relatively large pattern of about several tens of μm onto a substrate. Therefore, in the exposure apparatus, the numerical aperture (NA) of the projection optical system is changed to cope with patterns having various dimensions.

[0005] In an exposure apparatus, the resolution and the depth of focus are expressed by the following Expressions 1 and 2 using Rayleigh's formula, where k1 and k2 are constants. Resolution = k1 × λ / NA ··· (Expression 1) Depth of focus = k2 × λ / NA 2 ··· (Expression 2) Therefore, it can be seen that for a pattern with large dimensions, it is effective to reduce the NA to increase the depth of focus, and for a pattern with small dimensions, it is effective to increase the NA.

Prior Art Documents

Patent Documents

[0006]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0007] However, in order to change the NA of the optical system, when changing the aperture diameter of the diaphragm arranged near the pupil position of the optical system, depending on the size of the aperture diameter, the flow of the cooling gas for the optical element changes, and there is a risk of causing a decrease in optical performance due to fluctuations in the cooling effect.

[0008] The present invention has been made in view of such problems of the prior art, and an exemplary object thereof is to provide a technique advantageous for suppressing a decrease in the optical performance of a projection optical system.

Means for Solving the Problems

[0009] In order to achieve the above object, an exposure apparatus according to one aspect of the present invention is an exposure apparatus that exposes a substrate through a reticle, including a projection optical system that projects a pattern of the reticle onto the substrate, an NA diaphragm capable of changing the numerical aperture of the projection optical system, a temperature control unit that adjusts the temperature of the space inside the projection optical system and the temperature of the optical member arranged therein by supplying and discharging gas to and from the space inside the projection optical system, and a control unit that changes the conditions regarding the supply and discharge of the gas by the temperature control unit in accordance with the change in the numerical aperture by the NA diaphragm.

[0010] A further object or other aspect of the present invention will be clarified by the embodiments described below with reference to the accompanying drawings.

Advantages of the Invention

[0011] According to the present invention, for example, it is possible to provide a technology advantageous for suppressing a decrease in the optical performance of a projection optical system.

Brief Description of the Drawings

[0012]

Figure 1

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Embodiments for Carrying Out the Invention

[0013] Hereinafter, embodiments will be described in detail with reference to the accompanying drawings. Note that the following embodiments do not limit the invention according to the claims. Although a plurality of features are described in the embodiments, not all of these plurality of features are essential to the invention, and the plurality of features may be arbitrarily combined. Further, in the accompanying drawings, the same or similar configurations are denoted by the same reference numerals, and redundant descriptions are omitted.

[0014] FIG. 1 is a schematic diagram showing the configuration of an exposure apparatus 1000 as one aspect of the present invention. The exposure apparatus 1000 is used in a manufacturing process of a device such as a display device such as a television, a smartphone, a tablet terminal, or a semiconductor element, and is a lithography apparatus that forms a pattern on a substrate by exposing the substrate through a reticle (mask or reticle). In the present embodiment, the exposure apparatus 1000 performs a process (exposure process) of projecting a pattern formed on the reticle onto the substrate through a projection optical system and transferring the pattern of the reticle to the substrate.

[0015] The exposure apparatus 1000 is embodied, for example, as a so-called step-and-repeat type exposure apparatus (stepper) that fixes the reticle and transfers the pattern of the reticle to the substrate. Further, the exposure apparatus 1000 may be embodied as a so-called step-and-scan type exposure apparatus (scanner) that transfers the pattern of the reticle to the substrate while synchronously scanning the reticle and the substrate in the scanning direction with each other.

[0016] In this specification and the accompanying drawings, directions are indicated in an XYZ coordinate system in which a direction parallel to the surface on which the substrate is disposed is defined as the XY plane. Directions parallel to the X-axis, Y-axis, and Z-axis in the XYZ coordinate system are defined as the X-direction, Y-direction, and Z-direction, respectively, and rotations around the X-axis, Y-axis, and Z-axis are defined as θX, θY, and θZ, respectively.

[0017] As shown in FIG. 1, the exposure apparatus 1000 includes an illumination optical system 100, a reticle stage MS, a projection optical system 200, a substrate stage PS, a control unit 300, a console 400, and a temperature control unit 500.

[0018] The illumination optical system 100 is an optical system that illuminates the original plate M with light from the light source 101. As the light source 101, for example, a light source that emits ultraviolet rays such as an ultra-high pressure mercury lamp is used, but a KrF excimer laser, an ArF excimer laser, or the like may also be used. The light (exposure light) emitted from the light source 101 travels in the direction indicated by the arrow in FIG. 1.

[0019] The wavelength filter 102 has a function of transmitting light in a predetermined wavelength range and blocking light in a wavelength range outside the predetermined range. The ND filter 103 has a function of adjusting the intensity of the light emitted from the light source 101 to an appropriate intensity. The optical integrator 104 is an optical member for equalizing the illuminance distribution on the pattern surface of the original plate M. The light transmitted through the optical integrator 104 is condensed by the condenser lens 105.

[0020] A part of the light transmitted through the condenser lens 105 is split by the beam splitter 106 and enters the detection unit 107 that detects the intensity (light quantity) of the light. The detection unit 107 monitors whether the intensity of the light illuminating the original plate M is within a predetermined range, and is provided to control the light source 101 as necessary to stabilize the intensity of the light illuminating the original plate M.

[0021] The masking blade 108 is a blade for setting the range of the original plate M illuminated by the light from the light source 101 (the illumination area on the original plate). The lens 109 is a lens for imaging the illumination area set by the masking blade 108 on the original plate M. The light reflected by the reflection mirror 110 illuminates the original plate M while maintaining a predetermined angular distribution.

[0022] The original plate M is driven (scanned) in the X direction and the Y direction while being placed on the original plate stage MS. Further, a flat glass FM provided with a mark for focus measurement is disposed on the original plate stage MS. The original plate M includes a pattern surface on which a pattern to be transferred to the substrate P is drawn. The pattern of the original plate M is transferred to the substrate P on which the photosensitive agent is disposed via the projection optical system 200.

[0023] The projection optical system 200 is an optical system that projects the pattern of the original plate M onto the substrate P. In this embodiment, the projection optical system 200 is configured as an Offner type optical system. The projection optical system 200 includes, as a plurality of optical members (optical elements), a correction optical element 201, a trapezoidal mirror 202, a concave mirror 203, a meniscus lens 204, a convex mirror 205, and an NA aperture stop 206.

[0024] The correction optical element 201 is an optical element for correcting aberrations such as coma aberration, astigmatism, and distortion aberration. The trapezoidal mirror 202 reflects the light transmitted through the correction optical element 201 toward the concave mirror 203. The light reflected by the concave mirror 203 passes through the meniscus lens 204, is reflected by the convex mirror 205, and passes through the meniscus lens 204 again.

[0025] The NA aperture stop 206 is disposed at the pupil position (near the pupil position) of the projection optical system 200, and in this embodiment, it is disposed between the meniscus lens 204 and the convex mirror 205. The NA aperture stop 206 is composed of a variable aperture stop whose aperture diameter can be changed. The NA aperture stop 206 has a function of changing the numerical aperture (NA) of the projection optical system 200 by changing the aperture diameter. Further, in this embodiment, the meniscus lens 204, the convex mirror 205, and the NA aperture stop 206 constitute a convex mirror unit 210. The temperature of the internal space MSP of the convex mirror unit 210 and the temperature of the optical members disposed inside the convex mirror unit 210 are adjusted (temperature-controlled) by the temperature control unit 500.

[0026] The light transmitted through the meniscus lens 204 is reflected by the concave mirror 203 and the trapezoidal mirror 202 and reaches the substrate P. The substrate P is driven (scanned) in the X direction and the Y direction while being placed on the substrate stage PS, and is also driven in the Z direction as necessary. Further, a sensor FS for focus measurement is disposed on the substrate stage PS.

[0027] The control unit 300 is composed of a computer (information processing device) including, for example, a CPU and a memory. The control unit 300 comprehensively controls each part of the exposure apparatus 1000 according to a program stored in a storage unit or the like, and operates the exposure apparatus 1000. The console 400 is a unit for an operator (user) to operate the exposure apparatus 1000. When the operator inputs setting values such as the NA of the projection optical system 200 via the console 400, such setting values are sent to the control unit 300. Based on the setting value of the NA of the projection optical system 200 obtained from the console 400, the control unit 300 sends temperature control conditions for adjusting (temperature control) the temperature inside the projection optical system 200 and the temperature of the optical members arranged inside the projection optical system 200 to the temperature control unit 500.

[0028] The temperature control unit 500 is a temperature control device that adjusts the temperature of the space PSP inside the projection optical system 200 and the temperature of the optical members arranged inside the projection optical system 200 by supplying and discharging gas to and from the space PSP inside the projection optical system 200 via a supply port and a discharge port.

[0029] Referring to FIGS. 2 and 3, as an example of a method for measuring and evaluating the optical performance of the projection optical system 200, focus measurement executed in the exposure apparatus 1000 will be described. FIG. 2 is a diagram showing the positional relationship between the reticle stage MS and the substrate stage PS when focus measurement is executed. As shown in FIG. 2, when executing focus measurement for evaluating the focus performance of the projection optical system 200, the position of the reticle stage MS is adjusted so that the light (exposure light) from the illumination optical system 100 irradiates the flat glass FM arranged on the reticle stage MS. The light transmitted through the flat glass FM passes through the projection optical system 200 and reaches the substrate stage PS. At this time, the position of the substrate stage PS is adjusted so that the light reaching the substrate stage PS irradiates the sensor FS for focus measurement arranged on the substrate stage PS. When executing focus measurement, the focus performance of the projection optical system 200 is measured while driving the substrate stage PS in the Z direction.

[0030] FIG. 3(a) is a diagram showing an example of a mark for focus measurement provided on a flat glass FM. As shown in FIG. 3(a), on the flat glass FM, for example, four marks for focus measurement are provided, each of which has a pattern with different longitudinal directions by 45° and the same line width and the same pitch. Each mark includes a shielding portion (black portion) made of chromium and a transmissive portion (white portion). In the present embodiment, each of the four marks is identified by the angle (orientation) of the longitudinal direction of the pattern and is referred to as a 0° mark, a 45° mark, a 90° mark, and a 135° mark.

[0031] In focus measurement, light is irradiated onto each of the four marks provided on the flat glass FM, and the light from each of the four marks is made to enter a sensor FS for focus measurement. On the sensor FS for focus measurement, the same mark as the mark provided on the flat glass FM is provided. Specifically, on the sensor FS for focus measurement, four marks are provided in an arrangement that matches the orientation of each pattern of the four marks provided on the flat glass FM. For example, the light from the 0° mark (transmissive portion) provided on the flat glass FM passes through the 0° mark (transmissive portion) provided on the sensor FS for focus measurement. When the position where the mark provided on the flat glass FM is imaged via the projection optical system 200 coincides with the position of the mark provided on the sensor FS for focus measurement, the amount of light incident on and measured by the sensor FS for focus measurement becomes maximum.

[0032] FIG. 3(b) is a diagram showing an example of the result of actually performing focus measurement. The vertical axis represents the amount of light measured by the sensor FS for focus measurement, and the horizontal axis represents the focus position. FIG. 3(b) is obtained by selecting one mark from the four marks provided on the flat glass FM and plotting the amount of light measured by the sensor FS for focus measurement while driving the substrate stage PS in the Z direction. Referring to FIG. 3(b), the focus position at which the amount of light measured by the sensor FS for focus measurement is maximized can be determined (evaluated) as the optimal focus position. Also, by individually performing focus measurement for each mark provided on the flat glass FM, the optimal focus position for each mark can be determined.

[0033] Before explaining in detail the temperature control unit 500 in the present embodiment, a prior art for adjusting the temperature inside the projection optical system 200 and the temperature of the convex mirror 205 and the meniscus lens 204 arranged near the pupil position of the projection optical system 200 will be described.

[0034] FIGS. 12(a) and 12(b) are diagrams schematically showing the vicinity of the pupil of the projection optical system 200 to which the prior art is applied. FIG. 12(a) shows a state in which a high NA is set for the projection optical system 200 by increasing the aperture diameter of the NA stop 206, and FIG. 12(b) shows a state in which a low NA is set for the projection optical system 200 by decreasing the aperture diameter of the NA stop 206. Near the NA stop 206, a supply port 1207 for supplying a gas for air-cooling the region (space MSP) from the meniscus lens 204 to the convex mirror 205 and a discharge port 1208 for discharging the gas used for air-cooling are provided.

[0035] As shown in FIGS. 12(a) and 12(b), the gas supplied from the supply port 1207 forms a laminar flow along the NA aperture 206 toward the vicinity of the center and is discharged from the discharge port 1208. At this time, as shown in FIG. 12(a), when the aperture diameter of the NA aperture 206 is large, the gas supplied from the supply port 1207 diffuses after traveling a predetermined distance. On the other hand, as shown in FIG. 12(b), when the aperture diameter of the NA aperture 206 is small, the gas supplied from the supply port 1207 travels a relatively long distance along the NA aperture 206. Thus, the reach distance of the gas supplied from the supply port 1207 is different between the case where the aperture diameter of the NA aperture 206 is large and the case where the aperture diameter of the NA aperture 206 is small, and the cooling effect on the meniscus lens 204 and the convex mirror 205 varies depending on the NA.

[0036] With reference to FIGS. 13(a) and 13(b), the change in focus due to the exposure load (exposure heat) when the NA of the projection optical system 200 is different will be described. FIG. 13(a) is a diagram showing the result of focus measurement when the NA of the projection optical system 200 is large, and FIG. 13(b) is a diagram showing the result of focus measurement when the NA of the projection optical system 200 is small. In FIGS. 13(a) and 13(b), the vertical axis represents the focus, the horizontal axis represents the time (elapsed time) after the exposure light is incident on the projection optical system 200, and t0 is the start time of the incidence of the exposure light. The four curves indicated by F0°, F45°, F90°, and F135° respectively show the transition (change) of the focus with respect to the above-described 0° mark, 45° mark, 90° mark, and 135° mark.

[0037] Referring to FIGS. 13(a) and 13(b), as time elapses after exposure light is incident on the projection optical system 200, the focus changes. This is because the meniscus lens 204 is heated by the irradiation of the exposure light, and the refractive index of the meniscus lens 204 changes according to the temperature distribution generated in the meniscus lens 204. When the NA of the projection optical system 200 is small, since the gas from the supply port 1207 reaches the entire surface of the meniscus lens 204, the temperature change of the meniscus lens 204 becomes small. Therefore, since the change in the refractive index of the meniscus lens 204 is small, as shown in FIG. 13(b), the change in focus also becomes small. On the other hand, when the NA of the projection optical system 200 is large, it is difficult for the gas from the supply port 1207 to uniformly cool the entire surface of the meniscus lens 204, and the temperature change of the meniscus lens 204 becomes large. Therefore, the change in the refractive index of the meniscus lens 204 becomes large, and as shown in FIG. 13(a), the change in focus also becomes large. Thus, when the NA of the projection optical system 200 is large, the change in focus and the focus difference due to the orientation of the mark tend to be larger compared to the case where the NA of the projection optical system 200 is small.

[0038] As problems with such a phenomenon, two problems can be cited. The first problem is that in FIGS. 13(a) and 13(b), as shown by Shift, when the NA of the projection optical system 200 is large, the change in focus becomes larger compared to the case where the NA of the projection optical system 200 is small. The second problem is that in FIGS. 13(a) and 13(b), as shown by ΔF, the variation in focus becomes large among four marks (0° mark, 45° mark, 90° mark, and 135° mark) with different longitudinal directions of the pattern.

[0039] Therefore, in the present embodiment, a technique advantageous for solving the above-described two problems and suppressing a decrease in the optical performance of the projection optical system 200, particularly a decrease in focus performance, due to fluctuations in the cooling effect (temperature control effect) of the temperature control unit 500 is provided.

[0040] Referring to FIG. 4, the temperature control unit 500 in the present embodiment will be described in detail. FIG. 4 is a diagram showing the configuration of the temperature control unit 500 and the convex mirror unit 210. The temperature control unit 500 includes an air conditioner 501, supply pipes 505, 505a, 505b, and 505c, a plurality of supply ports 207a, 207b, and 207c, and a temperature control unit 508. Further, the temperature control unit 500 includes a temperature control supply unit 510, a plurality of discharge ports 208a, 208b, and 208c, discharge pipes 513a, 513b, 513c, and 516, and a discharge fan 515.

[0041] In the air conditioner 501, a gas whose temperature is stabilized by a chiller (not shown) is stored as a refrigerant. The air conditioner 501 has a function of controlling the temperature of the stored gas, and it is possible to control the temperature of such a gas to a desired temperature as necessary. The supply pipe 505 is supplied with a gas whose temperature is stabilized from the air conditioner 501. The supply pipe 505 includes, for example, a plurality of supply pipes 505a, 505b, and 505c through which the gas from the air conditioner 501 passes.

[0042] The temperature control unit 508 acquires information regarding the opening diameter of the NA aperture 206, that is, information regarding the NA of the projection optical system 200, from the control unit 300, and controls the temperature control supply unit 510 according to the conditions (temperature control conditions) regarding the supply and discharge of the gas by the temperature control unit 500. In the present embodiment, the temperature control unit 508 opens and closes each of the valves 511a, 511b, and 511c provided corresponding to the supply pipes 505a, 505b, and 505c. Further, the temperature control unit 508 operates mass flow controllers 512a, 512b, and 512c for adjusting the flow rate of the gas flowing through each of the supply pipes 505a, 505b, and 505c. The mass flow controllers 512a, 512b, and 512c can independently adjust the flow rate of the temperature-controlled gas under the control of the temperature control unit 508. The temperature-controlled gas supplied from the air conditioner 501 is sent to the internal space MSP of the convex mirror unit 210 through the supply pipes 505a, 505b, and 505c. Supply ports 207a, 207b, and 207c are connected to each of the supply pipes 505a, 505b, and 505c.

[0043] The supply ports 207a, 207b, and 207c are provided inside the convex mirror unit 210 to discharge (cool) heat from the meniscus lens 204, the convex mirror 205, and the space MSP between the meniscus lens 204 and the convex mirror 205. In the present embodiment, the supply ports 207a, 207b, and 207c are provided around the NA aperture 206 and are supply ports for supplying (blowing out) the gas from the air conditioner 501 to the space MSP.

[0044] By the temperature control unit 508 opening and closing the valves 511a, 511b, and 511c, it is possible to independently control (set) the presence or absence of gas supply (whether to supply gas) from each of the supply ports 207a, 207b, and 207c. Further, it is also possible to independently control (set) the supply amount of the gas supplied from each of the supply ports 207a, 207b, and 207c via the mass flow controllers 512a, 512b, and 512c.

[0045] In addition, actuators 209a, 209b, and 209c for driving the supply ports 207a, 207b, and 207c are provided at each of the supply ports 207a, 207b, and 207c. Therefore, it is possible to independently control (set) the positions (positions for supplying gas) of the supply ports 207a, 207b, and 207c via the actuators 209a, 209b, and 209c. Similarly, it is possible to independently control (set) the angles (angles in the direction of gas supply) of the supply ports 207a, 207b, and 207c via the actuators 209a, 209b, and 209c.

[0046] The discharge ports 208a, 208b, and 208c are discharge ports for discharging the gas supplied from the supply ports 207a, 207b, and 207c to the space MSP. The discharge ports 208a, 208b, and 208c are provided inside the convex mirror unit 210, around the NA aperture 206 in the present embodiment.

[0047] To each of the discharge ports 208a, 208b, and 208c, actuators 209d, 209e, and 209f for driving the discharge ports 208a, 208b, and 208c are provided. Therefore, it is possible to independently control (set) the positions (the positions for discharging gas) of the discharge ports 208a, 208b, and 208c via the actuators 209d, 209e, and 209f. Similarly, it is possible to independently control (set) the angles (the angles in the direction of discharging gas) of the discharge ports 208a, 208b, and 208c via the actuators 209d, 209e, and 209f.

[0048] To each of the discharge ports 208a, 208b, and 208c, discharge pipes 513a, 513b, and 513c are connected. In the present embodiment, the temperature control unit 508 opens and closes each of the valves 514a, 514b, and 514c provided corresponding to the discharge pipes 513a, 513b, and 513c. Thus, by the temperature control unit 508 opening and closing the valves 514a, 514b, and 514c, it is possible to independently control (set) the presence or absence of gas discharge (whether to discharge gas) from each of the discharge ports 208a, 208b, and 208c. Further, it is also possible to independently control (set) the discharge amount of the gas discharged from each of the discharge ports 208a, 208b, and 208c.

[0049] The gas discharged from the space MSP through the discharge ports 208a, 208b, and 208c reaches the discharge fan 515 through the discharge pipes 513a, 513b, and 513c. The gas that has reached the discharge fan 515 returns to the air conditioner 501 through the discharge pipe 516. The discharge fan 515 enables adjustment of the discharge performance and can maintain a sufficient discharge amount so that the gas containing heat does not stay in the space MSP inside the convex mirror unit 210.

[0050] Next, a determination method for determining temperature control conditions, which are conditions related to the supply and discharge of gas in the temperature control unit 500, will be described. In the present embodiment, the NA of the projection optical system 200 set by the NA aperture 206 is set as two NA conditions, the first numerical aperture NA1 and the second numerical aperture NA2, and the second numerical aperture NA2 is assumed to have a larger numerical aperture than the first numerical aperture NA1. Also, the number of temperature control conditions set for the temperature control unit 500 is assumed to be n types.

[0051] FIG. 5 is a diagram showing an example of temperature control conditions in the temperature control unit 500. Here, for simplicity of explanation, the number of supply ports for supplying gas to the space MSP inside the convex mirror unit 210 is three, namely supply ports a, b, and c, and the supply amounts of the gas supplied from each of the supply ports a, b, and c are three types: 0, 1, and 2. And the number of temperature control conditions set for the temperature control unit 500 is assumed to be nine (n = 9) on the premise of symmetric gas supply. However, actually, the number of supply ports, the supply amount of gas, the symmetry of gas supply, etc. are not limited to these. For example, the temperature control conditions may be the presence or absence of gas supply from each of a plurality of supply ports, the presence or absence of gas discharge from each of a plurality of discharge ports, the supply amount of gas supplied from each of a plurality of supply ports, the discharge amount of gas discharged from each of the plurality of discharge ports, etc. Also, the temperature control conditions may be the position of each of a plurality of supply ports, the position of each of a plurality of discharge ports, the angle of each of a plurality of supply ports, the angle of each of a plurality of discharge ports, the supply temperature of the gas, etc. Thus, the temperature control conditions include at least one of these conditions.

[0052] FIG. 6 is a flowchart for explaining a determination method for determining temperature control conditions, which are conditions related to the supply and discharge of gas in the temperature control unit 500. Such a determination method is executed, for example, by the control unit 300 included in the exposure apparatus 1000.

[0053] In S102, the NA of the projection optical system 200 is set to the first numerical aperture NA1 by the NA aperture 206.

[0054] In S103, the temperature control condition in the temperature control unit 500 is set to the first temperature control condition (the temperature control condition "NO.1" shown in FIG. 5), and in a state where exposure light is incident on the projection optical system 200 to apply an exposure load (heat load), focus measurement for measuring focus (change) is executed. In the present embodiment, focus measurement is continuously executed from the exposure light incident start time t0 until time t, and the amount of change in focus is the one at time t. Note that time t is set according to the time (for example, 10 hours) when focus (change) reaches an equilibrium state. Further, focus measurement is executed for a plurality of patterns having different longitudinal directions, specifically, for each of the 0° mark, 45° mark, 90° mark, and 135° mark shown in FIG. 3(a).

[0055] FIG. 7 is a diagram showing the result of focus measurement obtained in S103. In FIG. 7, the vertical axis represents focus, and the horizontal axis represents the time (elapsed time) since exposure light was incident on the projection optical system 200. The four curves indicated by F0°, F45°, F90°, and F135° respectively show the change in focus with respect to the 0° mark, 45° mark, 90° mark, and 135° mark described above. Further, the average of F0°, F45°, F90°, and F135° is defined as Shift, and the variation of F0°, F45°, F90°, and F135° is defined as ΔF.

[0056] In S104, the temperature control condition in the temperature control unit 500 is sequentially set to the second to nth temperature control conditions (n temperature control conditions are set), and for each temperature control condition, focus measurement is executed in a state where an exposure load (heat load) is applied.

[0057] In S105, the results of focus measurement obtained in S103 and S104, that is, the results of n times of focus measurement for n temperature control conditions are saved.

[0058] In S106, based on the results of the n focus measurements stored in S105, the temperature control conditions at the first numerical aperture NA1 are determined. Specifically, among the results of the n focus measurements, the temperature control condition (NO. n1) corresponding to the result where the focus difference (optical performance difference) due to the 0° mark, 45° mark, 90° mark, and 135° mark is minimized is set as the temperature control condition at the first numerical aperture NA1.

[0059] In S107, the NA of the projection optical system 200 is set to the second numerical aperture NA2 by the NA aperture 206.

[0060] In S108, similar to S103, the temperature control condition in the temperature control unit 500 is set to the first temperature control condition, and focus measurement for measuring the focus (change) is performed in a state where exposure light is incident on the projection optical system 200 to apply an exposure load (thermal load).

[0061] In S109, similar to S104, the temperature control condition in the temperature control unit 500 is sequentially set to the second to nth temperature control conditions (setting n temperature control conditions), and for each temperature control condition, focus measurement is performed in a state where an exposure load (thermal load) is applied.

[0062] In S110, the results of the focus measurement obtained in S108 and S109, that is, the results of the n focus measurements for n temperature control conditions are stored.

[0063] FIG. 8 is a diagram showing an example of the results of the focus measurement stored in S105 and S110, that is, an example of the results of the focus measurement at each of the first numerical aperture NA1 and the second numerical aperture NA2. In the present embodiment, as shown in FIG. 8, for each of the first numerical aperture NA1 and the second numerical aperture NA, the results of 9 focus measurements for 9 temperature control conditions of each mark (0° mark, 45° mark, 90° mark, and 135° mark) are obtained.

[0064] In S111, based on the results of the n - time focus measurements (Figure 8) saved in S105 and S110 respectively, the temperature - control conditions at the second numerical aperture NA2 are determined. Specifically, among the results of the n - time focus measurements for the second numerical aperture NA2, the temperature - control condition corresponding to the result closest to the result of the focus measurement corresponding to the temperature - control condition (NO.n1) at the first numerical aperture NA1 is set as the temperature - control condition at the second numerical aperture NA2. In other words, the temperature - control condition at the second numerical aperture NA2 is determined so that the focus difference between the focus in the equilibrium state before changing the NA of the projection optical system 200 (NA1) and the focus in the equilibrium state after changing the NA of the projection optical system 200 (NA2) is minimized.

[0065] In this embodiment, for example, let "NO.n2’" be a variable indicating the number (NO.) of the temperature - control condition. Then, the evaluation criterion ΔF(NA1 - NA2) shown in the following formula 3 is obtained. ΔF(NA2 - NA1)=sqrt{(F(0°, NA2, NO.n2’)-(F(0°, NA1, NO.n1)) 2 +(F(45°, NA2, NO.n2’)-(F(45°, NA1, NO.n1)) 2 +(F(90°, NA2, NO.n2’)-(F(90°, NA1, NO.n1)) 2 +(F(135°, NA2, NO.n2’)-(F(135°, NA1, NO.n1)) 2 ) ···(Formula 3) In formula 3, the condition under which the value of the evaluation criterion ΔF(NA2 - NA1) is minimized is the condition under which the optical performance difference (focus difference) between the first numerical aperture NA1 and the second numerical aperture NA2 is minimized, and such a temperature - control condition is set as the temperature - control condition (NO.n2) at the second numerical aperture NA2.

[0066] Thus, in this embodiment, while setting different NAs of NA1 and NA2 in the projection optical system 200 respectively, the optical performance (focus) of the projection optical system 200 is measured while changing the temperature control conditions (S101 to S105, S107 to S110 (first step)). Then, based on the optical performance difference (focus difference) between the measured optical performances, the temperature control conditions in the temperature control unit 500 are determined so that the optical performance difference (focus difference) between the first numerical aperture NA1 and the second numerical aperture NA2 becomes minimum (S106, S111 (second step)). Thereby, even when changing the NA of the projection optical system 200, it is possible to suppress a decrease in the optical performance of the projection optical system 200, particularly a decrease in the focus performance, due to fluctuations in the cooling effect (temperature control effect) of the temperature control unit 500.

[0067] Also, for each of the first numerical aperture NA1 and the second numerical aperture NA2, the temperature control conditions in the temperature control unit 500 may be determined so that the optical performance difference between the optical performances (focus) for each mark (0° mark, 45° mark, 90° mark, 135° mark) becomes minimum. In other words, the temperature control conditions are determined so that the focus difference between the focuses for each mark becomes minimum in each of the equilibrium state before changing the NA of the projection optical system 200 (NA1) and the equilibrium state after changing the NA of the projection optical system 200 (NA2).

[0068] FIG. 9 is a flowchart for explaining a determination method for determining temperature control conditions, which are conditions related to the supply and discharge of gas in the temperature control unit 500, for each NA of the projection optical system 200. Such a determination method is executed by, for example, the control unit 300 included in the exposure apparatus 1000. Note that since S202 to S205 and S207 to S210 are the same as S102 to S105 and S107 to S110 shown in FIG. 6, detailed description thereof is omitted here.

[0069] In S206, based on the results of the n - time focus measurements saved in S205, the temperature control condition at the first numerical aperture NA1 is determined. Specifically, among the results of the n - time focus measurements, the temperature control condition corresponding to the result where the focus difference (optical performance difference) due to the 0° mark, 45° mark, 90° mark, and 135° mark is minimized is set as the temperature control condition at the first numerical aperture NA1.

[0070] In S211, based on the results of the n - time focus measurements saved in S210, the temperature control condition at the second numerical aperture NA2 is determined. Specifically, among the results of the n - time focus measurements, the temperature control condition corresponding to the result where the focus difference (optical performance difference) due to the 0° mark, 45° mark, 90° mark, and 135° mark is minimized is set as the temperature control condition at the second numerical aperture NA2.

[0071] In this way, with different NA1 and NA2 respectively set for the projection optical system 200, while changing the temperature control condition, the optical performance (focus) of the projection optical system 200 for each mark is measured (S202 - S205, S207 - 210 (the first step)). Then, for each of the first numerical aperture NA1 and the second numerical aperture NA2, based on the optical performance difference (focus difference) between the measured optical performances, the temperature control condition in the temperature control unit 500 is determined so that such optical performance difference is minimized (S206, S211 (the second step)). Thereby, even when changing the NA of the projection optical system 200, it is possible to suppress a decrease in the optical performance of the projection optical system 200, particularly a decrease in the focus performance, due to fluctuations in the cooling effect (temperature control effect) of the temperature control unit 500.

[0072] In addition, as a result of intensive studies by the present inventors based on the flow of the determination method shown in FIG. 6, the study results shown in FIG. 10 were obtained. In FIG. 10, the vertical axis represents the evaluation criterion ΔF using Equation 3, and the horizontal axis represents the temperature control conditions for each of the first numerical aperture NA1 and the second numerical aperture NA2. Referring to FIG. 10, when the NA of the projection optical system 200 is changed from the first numerical aperture NA1 to the second numerical aperture NA2 (>NA1), if the supply amount of the gas from the temperature control unit 500 is increased, the evaluation criterion ΔF at the first numerical aperture NA1 and the second numerical aperture NA2 becomes smaller. This means that the difference in the change of focus becomes smaller at different NAs of the projection optical system 200. Therefore, when changing the numerical aperture of the projection optical system 200 from the first numerical aperture to the second numerical aperture larger than the first numerical aperture, the temperature control conditions in the temperature control unit 500 may be changed (determined) so that the supply amount of the gas supplied from the temperature control unit 500 to the space MSP increases.

[0073] In FIGS. 6 and 9, the determination method for determining the temperature control conditions in the temperature control unit 500 in the control unit 300 of the exposure apparatus 1000 was described. However, the temperature control conditions in the temperature control unit 500 can also be determined using a simulation mainly based on an information processing apparatus including a computer such as a computer.

[0074] FIG. 11 is a flowchart for explaining a determination method for determining the temperature control conditions in the temperature control unit 500 using an information processing apparatus. Similar to the above, the NA of the projection optical system 200 set by the NA aperture 206 is set as two NA conditions, the first numerical aperture NA1 and the second numerical aperture NA2, and the number of temperature control conditions set in the temperature control unit 500 is assumed to be n.

[0075] In S302, by causing exposure light to enter the projection optical system 200, a heat generation condition is set in which the optical member disposed inside the projection optical system 200 generates heat. Specifically, since a part of the exposure light is absorbed by the optical member, the amount of heat generation is calculated. Here, the optical member is intended to be the meniscus lens 204 and the convex mirror 205 included in the convex mirror unit 210 of the projection optical system 200.

[0076] In S303, temperature control conditions in the temperature control unit 500 are set with the NA of the projection optical system 200 being the first numerical aperture NA1, that is, the temperature control conditions at the first numerical aperture NA1 are set. As the temperature control conditions, for example, as shown in FIG. 5, they include the presence or absence of gas supply from each of the supply ports 207a, 207b, and 207c and the supply amount of the gas supplied from each of the supply ports 207a, 207b, and 207c.

[0077] In S304, the temperature control conditions set in S303 are applied to the convex mirror unit 210, and a thermal fluid simulation is executed in a state where an exposure load (thermal load) is applied to the projection optical system 200 to calculate the temperature distribution (thermal distribution) generated in the space MSP and the optical members. Specifically, these calculations can be performed by using software STREAM manufactured by HEXAGON, and the temperature distribution of the space MSP and the optical members in the equilibrium state can be obtained. However, the software used to calculate the temperature distribution is not limited to STREAM. Also, the space MSP is particularly intended for the space between the meniscus lens 204 and the convex mirror 205.

[0078] In S305, the temperature distribution calculated in S304 is converted into a refractive index distribution in the space MSP and the optical members, aberrations are obtained from such a refractive index distribution, and based on such aberrations, the focus, which is the optical performance of the projection optical system 200, is calculated. By obtaining aberrations from the refractive index distribution, it becomes possible to calculate focus performance such as ΔF and Shift shown in FIG. 7. At this time, focuses are calculated for a plurality of patterns whose longitudinal directions are different from each other, specifically, for each of the 0° mark, 45° mark, 90° mark, and 135° mark shown in FIG. 3(a).

[0079] In S306, for each of the n sets of temperature control conditions, S303, S304, and S305 are executed to calculate the focus.

[0080] In S307, based on the focus calculated in S306, the temperature control condition at the first numerical aperture NA1 is determined. Specifically, the temperature control condition at which the focus difference (optical performance difference) due to the 0° mark, 45° mark, 90° mark, and 135° mark is minimized is set as the temperature control condition at the first numerical aperture NA1.

[0081] In S308, the temperature control condition in the temperature control unit 500 with the NA of the projection optical system 200 being the second numerical aperture NA2, that is, the temperature control condition at the second numerical aperture NA2, is set.

[0082] In S309, similar to S304, the temperature control condition set in S308 is applied to the convex mirror unit 210, and a thermal fluid simulation is executed with an exposure load applied to the projection optical system 200 to calculate the temperature distribution generated in the space MSP and the optical member.

[0083] In S310, similar to S305, the temperature distribution calculated in S309 is converted into a refractive index distribution in the space MSP and the optical member, an aberration is obtained from such a refractive index distribution, and based on such an aberration, the focus, which is the optical performance of the projection optical system 200, is calculated.

[0084] In S311, similar to S306, for each of the n temperature control conditions, S308, S309, and S310 are executed to calculate the focus.

[0085] In S312, based on the foci calculated in S306 and S311, the temperature control condition at the second numerical aperture NA2 is determined. Specifically, in Equation 3, the condition at which the value of the evaluation criterion ΔF(NA2 - NA1) is minimized is the condition at which the optical performance difference (focus difference) between the first numerical aperture NA1 and the second numerical aperture NA2 is minimized, and such a temperature control condition is set as the temperature control condition at the second numerical aperture NA2.

[0086] Thus, for each of the different NA1 and NA2 of the projection optical system 200, the temperature distributions generated in the spatial MSP and the optical member are calculated by applying a thermal load to the projection optical system 200 (S303, S304, S308, S309 (first step)). Next, for each of the first numerical aperture NA1 and the second numerical aperture NA2, based on the refractive index distributions in the spatial MSP and the optical member obtained from the temperature distribution, the optical performance (focus) of the projection optical system 200 is calculated (S305, S306, S310, S311 (second step)). Then, based on the optical performance difference (focus difference) between the optical performances of the first numerical aperture NA1 and the second numerical aperture NA2, the temperature control conditions are determined (S307, S312 (third step)).

[0087] As described above, by determining the temperature control conditions in the temperature control unit 500 for the NA set in the projection optical system 200, in the exposure apparatus 1000, it becomes possible to change the temperature control conditions in the temperature control unit 500 in accordance with the change in the NA of the projection optical system 200 by the NA aperture 206. Therefore, when the NA of the projection optical system 200 is changed, it is possible to suppress a decrease in the optical performance of the projection optical system 200, particularly a decrease in the focus performance, due to fluctuations in the cooling effect (temperature control effect) of the temperature control unit 500. Note that the control (processing) for changing the temperature control conditions in the temperature control unit 500 in accordance with the change in the NA of the projection optical system 200 can be realized by the control unit 300.

[0088] The method for manufacturing an article according to an embodiment of the present invention is suitable for manufacturing articles such as semiconductor elements, liquid crystal display elements, flat panel displays, and MEMS. Such a manufacturing method includes a step of exposing a substrate coated with a photosensitive agent using the exposure apparatus 1000 described above, and a step of developing the exposed photosensitive agent. Further, an etching step, an ion implantation step, etc. are performed on the substrate using the pattern of the developed photosensitive agent as a mask, and a circuit pattern is formed on the substrate. By repeating these steps of exposure, development, etching, etc., a circuit pattern composed of a plurality of layers is formed on the substrate. In a subsequent process, dicing (processing) is performed on the substrate on which the circuit pattern is formed, and chip mounting, bonding, and inspection steps are performed. Further, such a manufacturing method may include other well-known steps (oxidation, film formation, vapor deposition, doping, planarization, resist stripping, etc.). The method for manufacturing an article in the present embodiment is advantageous in at least one of the performance, quality, productivity, and production cost of the article as compared with the prior art.

[0089] The present invention can also be realized by supplying a program that realizes one or more functions of the above-described embodiment to a system or apparatus via a network or a storage medium, and causing one or more processors in a computer of the system or apparatus to read and execute the program. Further, it can also be realized by a circuit (for example, ASIC) that realizes one or more functions.

[0090] The disclosure of this specification includes the following exposure apparatus, determination method, article manufacturing method, and program.

[0091] (Item 1) An exposure apparatus that exposes a substrate through a reticle, a projection optical system that projects the pattern of the reticle onto the substrate; an NA aperture whose numerical aperture of the projection optical system can be changed; a temperature control unit that adjusts the temperature of the space and the temperature of the optical members disposed inside by supplying and discharging gas to and from the space inside the projection optical system; A control unit that changes conditions regarding supply and discharge of the gas by the temperature control unit in accordance with a change in the numerical aperture by the NA aperture; An exposure apparatus, comprising:

[0092] (Item 2) The NA aperture is disposed at a pupil position of the projection optical system, The optical member includes a mirror and a lens disposed with the NA aperture therebetween, The temperature control unit supplies and discharges the gas to and from a space between the mirror and the lens, The exposure apparatus according to item 1, characterized in that.

[0093] (Item 3) The temperature control unit includes a plurality of supply ports for supplying the gas and a plurality of discharge ports for discharging the gas, The exposure apparatus according to item 1 or 2, characterized in that.

[0094] (Item 4) The conditions include at least one of presence or absence of supply of the gas from each of the plurality of supply ports, presence or absence of discharge of the gas from each of the plurality of discharge ports, supply amount of the gas supplied from each of the plurality of supply ports, discharge amount of the gas discharged from each of the plurality of discharge ports, position of each of the plurality of supply ports, position of each of the plurality of discharge ports, angle of each of the plurality of supply ports, angle of each of the plurality of discharge ports, and supply temperature of the gas, The exposure apparatus according to item 3, characterized in that.

[0095] (Item 5) The control unit changes the conditions based on a change in optical performance of the projection optical system caused by a change in the numerical aperture by the NA aperture, The exposure apparatus according to any one of items 1 to 4, characterized in that.

[0096] (Item 6) The optical performance includes focus, The control unit changes the condition so that the focus difference between the focus in the equilibrium state before changing the numerical aperture by the NA aperture and the focus in the equilibrium state after changing the numerical aperture by the NA aperture becomes minimum. The exposure apparatus according to item 5, characterized in that.

[0097] (Item 7) The optical performance includes focus, The control unit changes the condition so that the focus difference between the focuses for each of a plurality of patterns having different longitudinal directions in each of the equilibrium state before changing the numerical aperture by the NA aperture and the equilibrium state after changing the numerical aperture by the NA aperture becomes minimum. The exposure apparatus according to item 5, characterized in that.

[0098] (Item 8) The condition includes the supply amount for supplying the gas, When the control unit changes the numerical aperture from a first numerical aperture to a second numerical aperture larger than the first numerical aperture by the NA aperture, the control unit changes the condition so that the supply amount increases. The exposure apparatus according to any one of items 1 to 7, characterized in that.

[0099] (Item 9) A determination method for determining the conditions regarding the supply and discharge of gas in a temperature control unit that adjusts the temperature of the space inside the projection optical system that projects the original pattern onto the substrate and the temperature of the optical members arranged inside the space by performing the supply and discharge of gas to the space inside the projection optical system, A first step of measuring the optical performance of the projection optical system while changing the condition in a state where each of a plurality of different numerical apertures is set for the projection optical system by an NA aperture capable of changing the numerical aperture of the projection optical system; A second step of determining the condition based on the optical performance difference between the optical performances measured in a state where each of the plurality of numerical apertures is set; Having, characterized in that it is a determination method.

[0100] (Item 10) In the second step, the method for determination according to item 9, characterized in that the conditions are determined such that the optical performance difference is minimized.

[0101] (Item 11) A method for determining the conditions for supplying and discharging a gas to and from the space inside a projection optical system that projects a pattern of a master onto a substrate, for adjusting the temperature of the space and the temperature of the optical members arranged therein, comprising: In a state where a plurality of different numerical apertures are set for the projection optical system by an NA aperture whose numerical aperture can be changed, while changing the conditions, a first step of measuring the optical performance of the projection optical system for each of a plurality of patterns having different longitudinal directions; For each of the plurality of numerical apertures, a second step of determining the conditions based on the optical performance difference between the optical performances measured for each of the plurality of patterns; The method for determination, characterized by comprising the above.

[0102] (Item 12) In the second step, for each of the plurality of numerical apertures, the method for determination according to item 11, characterized in that the conditions are determined such that the optical performance difference is minimized.

[0103] (Item 13) A method for determining the conditions for supplying and discharging a gas to and from the space inside a projection optical system that projects a pattern of a master onto a substrate, for adjusting the temperature of the space and the temperature of the optical members arranged therein, comprising: For each of a plurality of different numerical apertures set for the projection optical system, a first step of calculating the temperature distribution generated in the space and the optical members by applying a thermal load to the projection optical system; For each of the plurality of numerical apertures, a second step of calculating the optical performance of the projection optical system based on the refractive index distribution in the space and the optical member obtained from the temperature distribution calculated in the first step; A third step of determining the conditions based on the optical performance difference between the optical performances of each of the plurality of numerical apertures calculated in the second step; A determination method, characterized by comprising:

[0104] (Item 14) In the third step, the conditions are determined such that the optical performance difference is minimized. The determination method according to item 13, characterized by this.

[0105] (Item 15) The optical performance includes focus. The determination method according to any one of items 9 to 14, characterized by this.

[0106] (Item 16) A step of exposing a substrate using the exposure apparatus according to any one of items 1 to 8; A step of developing the exposed substrate; A method for manufacturing an article, characterized by comprising:

[0107] (Item 17) A program characterized by causing a computer to execute the determination method according to any one of items 9 to 15.

[0108] The invention is not limited to the above embodiments, and various changes and modifications are possible without departing from the spirit and scope of the invention. Therefore, claims are attached to disclose the scope of the invention.

Explanation of Reference Numerals

[0109] 200: Projection optical system 204: Meniscus lens 205: Convex mirror 206: NA aperture stop 300: Control unit 1000: Exposure apparatus M: Original plate P: Substrate

Claims

Claim 1 An exposure apparatus for exposing a substrate through a reticle, comprising: a projection optical system that projects a pattern of the reticle onto the substrate; an NA aperture whose numerical aperture can be changed; a temperature control unit that adjusts the temperature of the space inside the projection optical system and the temperature of optical members disposed therein by supplying and discharging a gas to and from the space inside the projection optical system; a control unit that changes conditions regarding the supply and discharge of the gas by the temperature control unit in accordance with a change in the numerical aperture by the NA aperture; An exposure apparatus, characterized by comprising the above components. Claim 2 The NA aperture is disposed at a pupil position of the projection optical system, the optical members include a mirror and a lens disposed with the NA aperture therebetween, and the temperature control unit supplies and discharges the gas to and from a space between the mirror and the lens. The exposure apparatus according to claim 1, characterized by the above features. Claim 3 The exposure apparatus according to claim 1, characterized in that the temperature control unit includes a plurality of supply ports for supplying the gas and a plurality of discharge ports for discharging the gas. Claim 4 The conditions include at least one of the presence or absence of gas supply from each of the plurality of supply ports, the presence or absence of gas discharge from each of the plurality of discharge ports, the gas supply amount supplied from each of the plurality of supply ports, the gas discharge amount discharged from each of the plurality of discharge ports, the position of each of the plurality of supply ports, the position of each of the plurality of discharge ports, the angle of each of the plurality of supply ports, the angle of each of the plurality of discharge ports, and the gas supply temperature. The exposure apparatus according to claim 3, characterized by the above features. Claim 5 The exposure apparatus according to claim 1, characterized in that the control unit changes the conditions based on a change in the optical performance of the projection optical system caused by a change in the numerical aperture by the NA aperture. Claim 6 The optical performance includes focus, and the control unit changes the conditions such that a focus difference between the focus in an equilibrium state before changing the numerical aperture by the NA aperture and the focus in an equilibrium state after changing the numerical aperture by the NA aperture is minimized. The exposure apparatus according to claim 5, characterized by the above features. Claim 7 The optical performance includes focus, The control unit changes the condition so that the focus difference between the focuses for each of a plurality of patterns having different longitudinal directions is minimized in each of the equilibrium state before changing the numerical aperture by the NA aperture stop and the equilibrium state after changing the numerical aperture by the NA aperture stop. The exposure apparatus according to claim 5, wherein:

8. The condition includes a supply amount for supplying the gas. When the control unit changes the numerical aperture from a first numerical aperture to a second numerical aperture larger than the first numerical aperture by the NA aperture stop, the control unit changes the condition so that the supply amount increases. The exposure apparatus according to claim 1, wherein:

9. A determination method for determining conditions related to the supply and discharge of a gas to adjust the temperature of the space inside the projection optical system that projects the original pattern onto the substrate and the temperature of the optical members arranged inside, the method comprising: A first step of measuring the optical performance of the projection optical system while changing the condition in a state where each of a plurality of different numerical apertures is set for the projection optical system by an NA aperture stop capable of changing the numerical aperture of the projection optical system; A second step of determining the condition based on the optical performance difference between the optical performances measured in a state where each of the plurality of numerical apertures is set; The determination method characterized by including:

10. In the second step, the condition is determined so that the optical performance difference is minimized. The determination method according to claim 9, wherein:

11. A determination method for determining conditions related to the supply and discharge of a gas to adjust the temperature of the space inside the projection optical system that projects the original pattern onto the substrate and the temperature of the optical members arranged inside, the method comprising: A first step of measuring the optical performance of the projection optical system for each of a plurality of patterns having different longitudinal directions while changing the condition in a state where each of a plurality of different numerical apertures is set for the projection optical system by an NA aperture stop capable of changing the numerical aperture of the projection optical system; A second step of determining the condition based on the optical performance difference between the optical performances measured for each of the plurality of patterns for each of the plurality of numerical apertures; The determination method characterized by including:

12. The determination method according to claim 11, wherein in the second step, for each of the plurality of numerical apertures, the conditions are determined such that the optical performance difference is minimized.

13. A determination method for determining conditions regarding supply and discharge of a gas to and from a space inside a projection optical system that projects a pattern of a master onto a substrate, the method comprising: a first step of calculating a temperature distribution generated in the space and the optical member by applying a heat load to the projection optical system for each of a plurality of different numerical apertures set in the projection optical system; a second step of calculating an optical performance of the projection optical system based on a refractive index distribution in the space and the optical member obtained from the temperature distribution calculated in the first step for each of the plurality of numerical apertures; a third step of determining the conditions based on an optical performance difference between the optical performances of each of the plurality of numerical apertures calculated in the second step; The determination method characterized by including these steps.

14. The determination method according to claim 13, wherein in the third step, the conditions are determined such that the optical performance difference is minimized.

15. The determination method according to any one of claims 9, 11, and 13, wherein the optical performance includes focus.

16. A method for manufacturing an article, comprising: a step of exposing a substrate using the exposure apparatus according to any one of claims 1 to 8; and a step of developing the exposed substrate. The method is characterized by including these steps.

17. A program characterized by causing a computer to execute the determination method according to any one of claims 9, 11, and 13.

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