JP4537087B2 - Exposure apparatus and device manufacturing method - Google Patents

Description

  The present invention relates to an exposure apparatus that exposes an object to be processed such as a single crystal substrate for a semiconductor wafer and a glass substrate for a liquid crystal display (LCD). The present invention is particularly suitable for an exposure apparatus that performs exposure using ultraviolet rays or extreme ultraviolet (EUV) light as an exposure light source.

  When a fine semiconductor element such as a semiconductor memory or a logic circuit is manufactured using a photolithography technique, a circuit pattern drawn on a reticle or a mask (these terms are used interchangeably in this application). Conventionally, a reduction projection exposure apparatus that projects a circuit pattern by projecting the image onto a wafer or the like by a projection optical system has been used.

  The minimum dimension (resolution) that can be transferred by the reduction projection exposure apparatus is proportional to the wavelength of light used for exposure and inversely proportional to the numerical aperture (NA) of the projection optical system. Therefore, the shorter the wavelength, the better the resolution. For this reason, with the recent demand for miniaturization of semiconductor elements, the exposure light has been shortened, and an ultra-high pressure mercury lamp (i-line (wavelength: about 365 nm)), KrF excimer laser (wavelength: about 248 nm), ArF excimer. The wavelength of ultraviolet light used with lasers (wavelength about 193 nm) has become shorter.

  However, semiconductor elements are rapidly miniaturized, and there is a limit in lithography using ultraviolet light. Therefore, in order to efficiently transfer a very fine circuit pattern of 0.1 μm or less, a reduction projection exposure apparatus using extreme ultraviolet (EUV) light having a wavelength shorter than that of ultraviolet light and having a wavelength of about 10 nm to 15 nm ( Hereinafter, it is referred to as “EUV exposure apparatus”).

  As exposure light becomes shorter in wavelength, the absorption of light by a substance becomes very large. Therefore, it is difficult to use a refraction element utilizing refraction of light such as that used in visible light or ultraviolet light, that is, a lens. There is no glass material that can be used in the wavelength region of light, and a reflective optical system that uses only light reflection, that is, a mirror (for example, a multilayer mirror) to form an optical system is used.

  The mirror does not reflect all of the exposure light, but absorbs 30% or more of the exposure light incident on the mirror per mirror. The absorbed exposure light is divided into heat and deforms the surface shape of the mirror, causing deterioration of optical performance (particularly imaging performance). Therefore, the mirror is made of a low thermal expansion material having a very small linear expansion coefficient, for example, a linear expansion coefficient of 5 ppb / K, in order to reduce the change in the mirror shape due to temperature change.

  Since the EUV exposure apparatus uses light (EUV light) having a wavelength one order of magnitude smaller than that of conventional ultraviolet rays, the surface shape of the mirror needs to be deformed by an order of magnitude smaller than the conventional one, and is about 0.1 nm rms or less. Only deformation of is allowed. Therefore, even if the linear expansion coefficient of the mirror is 5 ppb / K, the temperature gradually increases and the shape of the mirror surface changes. For example, when the thickness of the mirror is 100 mm, the shape of the mirror surface changes by 0.1 nm (that is, an allowable limit) due to a temperature rise of 0.2 ° C.

Therefore, in Patent Document 1, the zero-crossing temperature (temperature at which the linear expansion coefficient becomes zero) of the material of at least one optical element that receives a thermal load during use is the average value of the manufacturing temperature and the average operating temperature of the element, An exposure apparatus is disclosed that is made from a low CTE material having a coefficient of thermal expansion such that the integral between the manufacturing temperature and the average operating temperature of the element is zero.
JP 2003-188097 A

  However, in the exposure apparatus of Patent Document 1, if the temperature of the optical element, that is, the mirror does not change during exposure or the like, the mirror can maintain an almost ideal shape, but if the temperature of the mirror changes, The mirror is deformed according to the linear expansion coefficient of the mirror, and as a result, the optical performance of the entire optical system is degraded.

  Therefore, the present invention reduces the influence of optical system performance degradation due to a change in mirror temperature in an exposure apparatus having an optical system including a plurality of mirrors using a material having a temperature at which the linear expansion coefficient becomes zero. An exemplary object of the present invention is to provide an exposure apparatus capable of performing the above.

In order to achieve the above object, an exposure apparatus according to one aspect of the present invention includes a plurality of optical elements using a material having a temperature at which the linear expansion coefficient becomes zero, and an original plate using the plurality of optical elements. In an exposure apparatus that includes a projection optical system that projects the pattern on the substrate, and controls and uses the temperature of the plurality of optical elements in the vicinity of the temperature at which the linear expansion coefficient becomes zero, each of the plurality of optical elements The control target temperature is set through the following steps (a) to (d).
(A) A step of setting a temperature of one optical element among the plurality of optical elements to a measured value of a temperature at which a linear expansion coefficient of a material of the one optical element becomes zero.
(B) A step of changing the temperature of the one optical element within the range of the measured value ± 1.0 degrees.
(C) measuring the aberration of the projection optical system after changing the temperature of the one optical element;
Steps (d) and (b) to (c) are repeated, and the temperature of the one optical element that minimizes the aberration of the projection optical system is set to the control target temperature of the one optical element. .

  Further objects and other features of the present invention will become apparent from the preferred embodiments described below with reference to the accompanying drawings.

  According to the exposure apparatus of the present invention, it is possible to provide an exposure apparatus that can realize desired optical performance by reducing deformation due to thermal expansion of an optical member that causes deterioration of imaging performance.

  Embodiments of the present invention will be described below with reference to the drawings.

  Hereinafter, an exposure apparatus which is an exemplary embodiment of the present invention will be described with reference to the accompanying drawings. Here, FIG. 1 is a schematic block diagram showing an exposure apparatus 500 as one aspect of the present invention.

  Hereinafter, an exemplary exposure apparatus 500 to which the present invention is applied will be described with reference to FIG.

  The exposure apparatus 500 of the present invention uses EUV light (light having a wavelength of 13 to 14 nm, for example, a wavelength of 13.4 nm) as illumination light for exposure, for example, a step-and-scan method or a step-and-repeat method. The projection exposure apparatus exposes the circuit pattern formed on the mask 520 to the object 540. Such an exposure apparatus is suitable for a lithography process of sub-micron or quarter micron or less, and in the present embodiment, a step-and-scan type exposure apparatus (also referred to as “scanner”) will be described as an example. Here, the “step and scan method” means that the wafer is continuously scanned (scanned) with respect to the mask to expose the mask pattern onto the wafer, and the wafer is stepped after the exposure of one shot is completed. The exposure method moves to the next exposure area. The “step-and-repeat method” is an exposure method in which the wafer is stepped and moved to the exposure area of the next shot for every batch exposure of the wafer.

  Referring to FIG. 1, an exposure apparatus 500 includes an illumination apparatus 510, a mask stage 525 on which a mask 520 is placed, a projection optical system 530, a wafer stage 545 on which an object 540 is placed, and an alignment detection mechanism. 550 and a focus position detection mechanism 560.

  Further, as shown in FIG. 1, since EUV light has a low transmittance with respect to the atmosphere, at least an optical path through which the EUV light passes (that is, the entire optical system) is a vacuum atmosphere VC.

  The illumination device 510 is an illumination device that illuminates the mask 520 with arc-shaped EUV light (for example, wavelength 13.4 nm) with respect to the arc-shaped field of the projection optical system 530. The illumination device 510 includes an EUV light source 512, an illumination optical system 514, and the like. Have

  As the EUV light source 512, for example, a laser plasma light source is used. In this method, a target material in a vacuum vessel is irradiated with high-intensity pulsed laser light to generate high-temperature plasma, and EUV light having a wavelength of, for example, about 13 nm is emitted from the target material. As the target material, a metal film, a gas jet, a droplet, or the like is used. In order to increase the average intensity of the emitted EUV light, the repetition frequency of the pulse laser should be high, and it is usually operated at a repetition frequency of several kHz.

  The illumination optical system 514 includes a condenser mirror 514a (which may be a concave mirror or a convex mirror) and an optical integrator 514b. The condensing mirror 514a collects EUV light emitted from the laser plasma almost isotropically. The optical integrator 514b has a role of uniformly illuminating the mask 520 with a predetermined numerical aperture.

  The mask 520 is a reflective mask on which a circuit pattern (or image) to be transferred is formed. The mask 520 is supported and fixed to the mask stage using an electrostatic chuck or the like, and is driven integrally with the mask stage. The diffracted light emitted from the mask 520 is reflected by the projection optical system 530 and projected onto the object to be processed 540. The mask 520 and the object to be processed 540 are arranged so as to have an optically conjugate relationship. Since the exposure apparatus 500 is a step-and-scan exposure apparatus, the pattern of the mask 520 is reduced and projected onto the object 540 by scanning the mask 520 and the object 540.

  The mask stage 525 supports the mask 520 and is connected to a moving mechanism (not shown). The mask stage 525 may employ any structure known in the art. A moving mechanism (not shown) is configured by a linear motor or the like, and can move the mask 520 by driving the mask stage 525 at least in the X direction. The exposure apparatus 500 scans the mask 520 and the workpiece 540 in synchronization with each other in consideration of the magnification of the projection optical system. Here, X is a scanning direction within the surface of the mask 520 or the object to be processed 540, Y is a direction perpendicular thereto, and Z is a direction substantially perpendicular to the surface of the mask 520 or the object to be processed 540.

  The projection optical system 530 uses a plurality of reflection mirrors (that is, multilayer mirrors) to reduce and project the pattern on the mask 520 surface onto the object to be processed 540 that is an image plane. The number of the plurality of mirrors is about 4 to 8 (preferably an even number such as 4, 6, 8, etc.). FIG. 1 shows an example of four mirror systems M1, M2, M3, and M4 in the order in which light is reflected from the mask side. In order to realize a wide exposure area with a small number of mirrors, such as 4 to 6, a mask 520 and an object to be processed using only a thin arc-shaped area (ring field) separated from the optical axis by a certain distance. By simultaneously scanning 540, the pattern on the mask surface is transferred to a large area on the object to be processed. The numerical aperture (NA) of the projection optical system 530 is about 0.2 to 0.3.

  The object to be processed 540 is a wafer in the present embodiment, but widely includes liquid crystal substrates and other objects to be processed. A photoresist is applied to the object to be processed 540. The photoresist coating process includes a pretreatment, an adhesion improver coating process, a photoresist coating process, and a prebaking process. Pretreatment includes washing, drying and the like. The adhesion improver coating process is a surface modification process for improving the adhesion between the photoresist and the base (that is, a hydrophobic process by application of a surfactant). Coat or steam. Pre-baking is a baking (baking) step, but is softer than that after development, and removes the solvent.

  Wafer stage 545 supports object 540 to be processed by wafer chuck 545a. For example, the wafer stage 545 moves the object 540 in the XYZ directions using a linear motor. The wafer stage 545 on which the object to be processed 540 is placed is scanned in synchronization with the aforementioned mask stage in consideration of the projection magnification of the projection optical system. Further, the position of the mask stage 525 and the position of the wafer stage 545 are monitored by, for example, a laser interferometer or the like, and both are driven at a constant speed ratio.

  The alignment detection mechanism 550 measures the positional relationship between the position of the mask 520 and the optical axis of the projection optical system 530, and the positional relationship between the position of the object 540 and the optical axis of the projection optical system 530, and The positions and angles of the mask stage 525 and the wafer stage 545 are set so that the projected image coincides with a predetermined position of the object 540 to be processed.

  The focus position detection mechanism 560 measures the focus position in the Z direction on the surface of the object to be processed 540 and controls the position and angle of the wafer stage 545, so that the surface of the object to be processed 540 is always projected by the projection optical system 530 during exposure. Keep at the imaging position.

  In the exposure, the EUV light emitted from the illumination device 510 illuminates the mask 520 and forms a pattern on the surface of the mask 520 on the surface of the object to be processed 540. In the present embodiment, the image surface is an arc-shaped (ring-shaped) image surface, and the entire surface of the mask 520 is exposed by scanning the mask 520 and the object to be processed 540 at the speed ratio of the reduction ratio.

  Next, the characteristics of the linear expansion coefficient of each mirror material of the projection optical system 530 in FIG. 1 and the temperature of each mirror will be described with reference to FIGS.

  FIG. 2 is a diagram illustrating an example of the temperature dependence of the linear expansion coefficient of the mirror material, in which the horizontal axis represents temperature T (° C.) and the vertical axis represents linear expansion coefficient CTE (Coefficient of Thermal Expansion). The mirror material used in the present invention has a temperature at which the linear expansion coefficient CTE becomes zero, and the temperature is denoted as Tz (° C.).

The linear expansion coefficient CTE changes almost linearly at a temperature near Tz (° C.).
For example, in the case of a material with Tz = 23.0 ° C. and a slope of −1.25 [ppb / K / K],
It is approximated by CTE = −1.25 × (T−23.0) [ppb / K]. In that case, by controlling the mirror temperature in the vicinity of 23.0 ° C. (within 23 ± 1 ° C., more preferably within 23 ± 0.5 ° C.), deformation due to heat can be reduced.

  When the mirror temperature deviates from Tz, the amount of deformation due to temperature change (heat) increases, and the amount of aberration generated thereby increases.

  FIG. 3 is a diagram showing a measured value Tzm of the temperature at which the linear expansion coefficient of each mirror of the projection optical system of the present embodiment becomes zero, and a control target temperature Tc when the mirror is temperature-controlled. M1 to M4 represent first to fourth mirrors, respectively. For the sake of simplicity, description will be made assuming that the mirror deformation due to exposure is minimized when the control target temperature Tc is matched with the temperature at which the linear expansion coefficient becomes zero.

  As shown in FIG. 3, the control target temperature Tc of each mirror is set to a value different from the measured value Tzm of the temperature at which the linear expansion coefficient becomes zero. The reason is that there is a measurement error of about 1 ° C. (0.5 ° C.) in Tzm, and if the control target temperature Tc is made equal to Tzm, the mirror is deformed and aberration is generated.

  The procedure for setting Tc in this embodiment will be described with reference to FIGS. FIG. 4 is a diagram showing the relationship between the control target temperature of the mirror M1 and the aberration generated in the projection optical system. The horizontal axis represents the mirror control temperature, and the vertical axis represents the wavefront aberration (RMS value) WFR of the projection optical system. The control temperature of the first mirror M1 is set to the measured value Tzm (M1) of the temperature at which the linear expansion coefficient of the first mirror M1 becomes zero as an initial value, and the wavefront aberration WFR is measured by changing the control temperature. repeat. As a result, the control temperature at which the wavefront aberration is minimized is known, and the temperature Tc (M1) is set as the control target temperature of the mirror M1.

  Next, the control target temperature of the second mirror M2 is set in the same procedure. The initial value is set to the measured value Tzm (M2) of the temperature at which the linear expansion coefficient of the second mirror M2 becomes zero, and the measurement of the wavefront aberration WFR is repeated while changing the control temperature. As a result, the control temperature at which the wavefront aberration is minimized is known, and the temperature Tc (M2) is set as the control target temperature of the mirror M2. The relationship between the control target temperature of the second mirror M2 and the aberration of the projection optical system is shown in FIG. The meaning of the symbols is the same as in FIG.

  As described above, the control target temperature Tc is determined and set for the first mirror M1 and the second mirror M2. The control target temperature Tc is determined and set for the third mirror M3 and the fourth mirror M4 in the same procedure. Although the control target temperature Tc is set for all the four mirrors M1 to M4 as described above, the above procedure may be further repeated in order to further reduce the aberration. Further, the control target temperature Tc does not necessarily have to be set for all the mirrors by the above procedure, and may be omitted as necessary.

  Here, as described above, Tzm is a measurement value obtained by measuring the temperature at which the CTE becomes zero. However, it is very difficult to accurately measure the temperature at which the CTE becomes zero. There may be an error within 0 degree (within 0.5 degree). Therefore, the control temperature of the mirror may be changed so that only specific aberrations such as spherical aberration, coma aberration, field curvature, distortion aberration, astigmatism, etc. are seen, instead of wavefront aberration (or wavefront aberration). When the wavefront is approximated to a Zernike polynomial, only the coefficient of a specific term may be viewed, or a combination thereof may be viewed.) When examining the mirror, the control temperature of the mirror is Tzm. It is desirable to change within a range of ± 1.0 degree (or 0.5 degree). In other words, the control target temperature Tc is set within 2 degrees (more preferably within 1 degree, more preferably within 0.5 degree) from the temperature Tz at which the CTE becomes zero.

  Moreover, about the 1st mirror which receives the light of the largest light quantity among said 1st-4th mirror, in order to absorb the heat | fever of the largest calorie | heat amount, compared with the other 2-4 mirrors, When the control target temperature Tc is brought close to the temperature at which the CTE of the material of the first mirror becomes zero, the performance change of the optical system with respect to the temperature change can be further reduced. Therefore, in order to suppress the deformation amount when the first mirror M1 is deformed by receiving heat, the control target temperature of the first mirror M1 is determined by the above procedure, and as a result, as described above, the first mirror M1 is determined. The deviation of the control target temperature of M1 from the temperature at which CTE becomes zero may be within 2 degrees (more preferably within 1 degree, more preferably within 0.5 degree). Further, for the second mirror M2 that absorbs the second most heat, it is desirable to determine the control target temperature Tc by the above procedure in order to reduce the deformation amount of the mirror M2. Of course, the control target temperature may be determined by the above procedure for all the mirrors included in the projection optical system, or the mirror may be selectively extracted and the control target temperature may be determined for the mirror by the above procedure. Here, the first mirror or the first and second mirrors are selected, but the light received is selected in descending order. In addition to this, even if the control target temperature is set based on the above procedure for a mirror that is not preferable to be deformed due to optical performance (particularly, the mirror closest to the substrate or wafer in the optical path of exposure light). I do not care.

  Of course, the present invention is not limited to this. For the first mirror (the mirror closest to the reticle or mask on the optical path) that receives the largest amount of light, or at least one mirror from the reticle side on the optical path, the amount of deformation due to temperature change is reduced. Therefore, the control target temperature Tc is set to a value close to the temperature Tz at which the CTE becomes zero (preferably Tc−0.5 degrees or more and Tc + 0.5 degrees or less), and then the fourth mirror (on the optical path, with the smallest received light amount). For the mirror closest to the substrate or wafer) or at least one mirror from the substrate on the optical path, the control target temperature Tc may be set so as to reduce (preferably minimize) the aforementioned wavefront aberration. I do not care.

  Moreover, in the said Example, although the control target temperature of each mirror M1-M4 is mutually different, of course, it is not this limitation, and all the control target temperature of each mirror M1-M4 may be the same. Preferably, the difference between the highest value and the lowest value among the control target temperatures of the mirrors M1 to M4 is within 2 degrees, more preferably 1 degree, and even more preferably within 0.5 degrees. If the temperature at which the linear expansion coefficient of all the mirrors becomes zero is not exactly the same, the control target temperature of at least one of all the mirrors is different from the control target temperature of the other mirrors. It is desirable to control the temperature (so that the difference between the maximum value and the minimum value of the control target temperature is 0.1 degrees or more, more preferably 0.3 degrees or more).

  In addition, what was shown in FIG. 8 is a figure which shows an example of the mirror temperature control mechanism of a present Example. A temperature sensor that measures the temperature of the mirror, a mirror temperature controller that controls the temperature of the mirror based on the measurement result of the temperature sensor, and a Peltier element that applies a predetermined voltage to the Peltier element according to a command from the mirror temperature controller A control unit, a Peltier element controlled by the Peltier element control unit, a cooling jacket in contact with the Peltier element (this cooling jacket is substantially kept at a constant temperature), and a temperature of the cooling jacket A heat medium circulation device that circulates a heat medium that controls the heat medium, and a radiation plate (radiation member) provided in contact with a surface (opposite surface) different from the cooling jacket with respect to the Peltier element described above. By arranging the radiation plate opposite to the back side (which may be the front side or side) of the optical member (mirror), the radiation from the radiation plate can be reduced. It is under the control of the temperature of the optical element (mirror) Te.

  Next, an embodiment of a device manufacturing method using the above-described exposure apparatus 500 will be described with reference to FIGS. FIG. 6 is a flowchart for explaining how to fabricate devices (ie, semiconductor chips such as IC and LSI, LCDs, CCDs, and the like). In the present embodiment, the manufacture of a semiconductor chip will be described as an example. In step 1 (circuit design), a device circuit is designed. In step 2 (mask production), a mask on which the designed circuit pattern is formed is produced. In step 3 (wafer manufacture), a wafer is manufactured using a material such as silicon. Step 4 (wafer process) is called a pre-process, and an actual circuit is formed on the wafer by lithography using the mask and the wafer. Step 5 (assembly) is called a post-process, and is a process for forming a semiconductor chip using the wafer created in step 4. The assembly process (dicing, bonding), packaging process (chip encapsulation), and the like are performed. Including. In step 6 (inspection), inspections such as an operation confirmation test and a durability test of the semiconductor device created in step 5 are performed. Through these steps, a semiconductor device is completed and shipped (step 7).

  FIG. 7 is a detailed flowchart of the wafer process in Step 4. In step 11 (oxidation), the surface of the wafer is oxidized. In step 12 (CVD), an insulating film is formed on the surface of the wafer. In step 13 (electrode formation), an electrode is formed on the wafer by vapor deposition or the like. Step 14 (ion implantation) implants ions into the wafer. In step 15 (resist process), a photosensitive agent is applied to the wafer. Step 16 (exposure) uses the exposure apparatus 500 to expose a circuit pattern on the mask onto the wafer. In step 17 (development), the exposed wafer is developed. In step 18 (etching), portions other than the developed resist image are removed. In step 19 (resist stripping), the resist that has become unnecessary after the etching is removed. By repeatedly performing these steps, multiple circuit patterns are formed on the wafer. According to the device manufacturing method of the present embodiment, it is possible to manufacture a higher quality device than before. Thus, the device manufacturing method using the exposure apparatus 500 and the resulting device also constitute one aspect of the present invention.

The preferred embodiments of the present invention have been described above, but the present invention is not limited to these embodiments, and various modifications and changes can be made within the scope of the gist. For example, the present invention can also be applied to an exposure apparatus including a reflecting mirror that exposes light other than EUV light, such as g-line, h-line, i-line, KrF excimer laser, ArF excimer laser, and F ₂ laser. Further, it can be applied not only to the imaging mirror of the projection optical system but also to a mask. Further, it can be applied not only to the projection optical system but also to the illumination optical system. In the embodiment, the control target temperature is determined so that the wavefront aberration is reduced as the aberration. However, the control target temperature is set so that the distortion is reduced as the aberration particularly in the mirror close to the object plane, the image plane, or the intermediate imaging position. May be determined.

1 is a schematic block diagram showing an exemplary embodiment of an exposure apparatus as one aspect of the present invention. It is a figure which shows the example of the temperature dependence of the linear expansion coefficient of mirror material. It is a figure which shows the measured value of the temperature from which the linear expansion coefficient of four mirrors becomes zero, and the control target temperature of a mirror. It is a figure which shows the control target temperature of the 1st mirror M1, and the relationship of an aberration. It is a figure which shows the control target temperature of the 2nd mirror M2, and the relationship of an aberration. It is a flowchart for demonstrating manufacture of devices (semiconductor chips, such as IC and LSI, LCD, CCD, etc.). 7 is a detailed flowchart of the wafer process in Step 4 shown in FIG. 6. It is an example of a cooling mechanism.

Explanation of symbols

500 Exposure Device 510 Illumination Device 512 EUV Light Source 514 Illumination Optical System 520 Mask 530 Projection Optical System M1 First Mirror M2 Second Mirror M3 Third Mirror M4 Fourth Mirror Tzm Measured value of temperature at which the linear expansion coefficient becomes zero Tc Mirror Control target temperature CTE Linear expansion coefficient

Claims (4)

A plurality of optical elements using a material having a temperature at which the linear expansion coefficient is zero, and a projection optical system that projects a pattern of an original on a substrate using the plurality of optical elements, wherein the linear expansion coefficient is in an exposure apparatus used to control the temperature of the plurality of optical elements to a temperature near to zero, it sets through said plurality of optical elements following the respective control target temperature of (a) ~ (d) step An exposure apparatus characterized by that.
(A) the step of setting the temperature of one optical element among the plurality of optical elements to a measured value at which the linear expansion coefficient of the material of the one optical element is zero;
( B ) changing the temperature of the one optical element within a range of the measured value ± 1.0 degrees ;
( C ) measuring the aberration of the projection optical system after changing the temperature of the one optical element;
The steps ( d ) and ( b ) to ( c ) are repeated , and the temperature of the one optical element that minimizes the aberration of the projection optical system is set to the control target temperature of the one optical element. Process. Using 14nm or less EUV light over a wavelength 13 nm, the exposure apparatus according to claim 1 Oh wherein Rukoto by the plurality of optical elements are all reflecting optical element. 3. A device manufacturing method comprising: an exposure step of exposing the substrate using the exposure apparatus according to claim 1; and a developing step of developing the exposed substrate. A plurality of optical elements using a material having a temperature at which the linear expansion coefficient is zero, and a projection optical system that projects a pattern of an original on a substrate using the plurality of optical elements, wherein the linear expansion coefficient is in an exposure apparatus used to control the temperature of the plurality of optical elements to a temperature near to zero, it sets through said plurality of optical elements following the respective control target temperature of (a) ~ (d) step A control target temperature setting method .
(A) the step of setting the temperature of one optical element among the plurality of optical elements to a measured value at which the linear expansion coefficient of the material of the one optical element is zero;
( B ) changing the temperature of the one optical element within a range of the measured value ± 1.0 degrees ;
( C ) measuring the aberration of the projection optical system after changing the temperature of the one optical element;
The steps ( d ) and ( b ) to ( c ) are repeated , and the temperature of the one optical element that minimizes the aberration of the projection optical system is set to the control target temperature of the one optical element. Process.

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