JP3770352B2 - Optical axis adjustment method for exposure apparatus - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an optical axis adjustment method for an exposure apparatus, and more particularly to an optical axis adjustment method for an exposure apparatus that includes an exposure apparatus body unit, a light source unit, and a relay optical system unit that connects the two units.
[0002]
[Prior art]
As an exposure light source of an exposure apparatus (for example, a stepper or the like) used in manufacturing a semiconductor element, a liquid crystal display element or the like in a lithography process, a mercury lamp has been conventionally used. In order to shorten the wavelength, a KrF excimer laser or the like has come to be used.
[0003]
In general, an exposure apparatus using an excimer laser as an exposure light source is roughly divided into an exposure apparatus main unit composed of a chamber in which the main body of the exposure apparatus is accommodated, a light source unit composed of an excimer laser apparatus, and these are optically coupled and physically connected. Are composed of three blocks of a relay optical system unit (beam matching unit). Each unit weighs several hundred kilos to several tons, the relay optical system unit is approximately 300 kg, the excimer laser apparatus is approximately 1 ton, and the exposure apparatus main unit is more than that.
[0004]
These units are assembled once before shipment from the factory, and the optical axis is adjusted between units to confirm that they are operating normally. After disassembling and packing each unit, the unit is assembled and installed at the destination. It is carried out.
[0005]
When installing this apparatus, each unit was installed in a general place, the optical system cover of each unit was removed, and the optical axis adjustment performed before factory shipment was performed again according to the installation state of the apparatus. The optical axis is adjusted by removing the optical system cover of each unit and repeatedly adjusting the optical member for adjusting the optical axis tilt and displacement based on the operator's intuition and experience using a helium neon laser. Had gone by.
[0006]
[Problems to be solved by the invention]
As described above, each unit of the exposure apparatus is heavy, and in order to install these units so that the optical axes between the units coincide with each other, it is necessary to install each unit within a range that can be adjusted by the optical member. Therefore, it is difficult to position the unit, and the work of adjusting the optical member using the above helium neon laser requires skill, and it is necessary to repeat trial and error, The workability was poor, and there were inconveniences that it was troublesome and time consuming.
[0007]
In addition to this, in the case of an apparatus using an excimer laser as a light source, nitrogen gas or the like is sealed in order to prevent generation of cloudy substances in the optical system due to the photochemical reaction of the excimer laser during exposure. However, when adjusting the optical axis, it is necessary to open the cover of each unit, so that there is a disadvantage that the nitrogen gas leaks.
[0008]
The present invention has been made under such circumstances, and an object of the present invention is to adjust the optical axis between the units constituting the exposure apparatus easily and accurately. It is to provide a method.
[0009]
[Means for Solving the Problems]
The invention according to claim 1 is emitted from the exposure apparatus main unit (12), the light source unit (14) separately from the exposure apparatus main unit (12), and the light source in the light source unit (14). In the optical axis adjustment method of the exposure apparatus (10) comprising the relay optical system unit (16) for guiding the light to the illumination optical system (18) in the exposure apparatus body unit (12) and connecting the two units. The exposure apparatus main unit (12) and the light source unit (14) are respectively installed at predetermined installation positions, and at least two of the three known positional relationships with respect to the reference point on the optical axis of each unit are known. Each of the dimensional coordinates is measured and then the relay optical system unit (16) is connected to the exposure apparatus main unit (12) and the light source unit (14) in the relay optical system. Measure the three-dimensional coordinates of at least two points whose positional relationship with the reference point on the optical axis of the unit (16) is known, and based on each measurement result, the remaining two units with respect to the optical axis of any unit By calculating the inclination and shift amount of the optical axis, and adjusting the optical members (22, 24, 26, 28, 30, 32) incorporated in at least one of the three units based on the calculation results, 3 It is characterized by aligning the optical axes of two units.
[0010]
According to this, the exposure apparatus main body unit and the light source unit are respectively installed at predetermined installation positions, and at least two three-dimensional known positional relationships with respect to the reference point on the optical axis of each unit for both units. The coordinates are measured, and then, with the exposure apparatus main unit and the light source unit connected by the relay optical system unit, at least two known positional relationships with the reference point on the optical axis of the relay optical system unit are known. Three-dimensional coordinates are measured. Then, the inclination and shift amount of the optical axes of the remaining two units with respect to the optical axis of any unit are calculated based on the measured three-dimensional coordinates of each unit. Then, based on the calculated tilt and shift amount of the optical axis, the optical members of at least one of the three units are adjusted to align the optical axes of the three units. As described above, according to the present invention, the optical axis inclination and the shift amount (positional deviation) between the units are calculated based on the measurement results of the two-dimensional three-dimensional coordinate positions for each unit, and light is calculated based on the results. Because the method of adjusting the axis manually or automatically is adopted, it is necessary to open the cover of each unit unlike the conventional case where the optical member is adjusted repeatedly based on the intuition and experience of the operator. In addition, the optical axis can be adjusted easily and accurately.
[0011]
In this case, the method for measuring the three-dimensional coordinate positions of at least two points for each unit is not particularly limited. For example, as in the invention described in claim 2, at least two points of the three-dimensional coordinates of each unit. The measurement of the coordinates may be performed using an optical measuring device (46) that targets the reflecting plates (42a, 42b, 42c, 42d, 42e, 42f). In this case, since the three-dimensional coordinates of at least two points of each unit are optically measured using the reflector as a target, three-dimensional coordinate values can be obtained very precisely, and the optical axis can be adjusted accurately. become able to. For example, when a total station or the like having a coordinate measurement function and a calculation function is used as a measurement device, most of the optical axis adjustment work can be automated.
[0012]
In the first aspect of the present invention, the type of the light source unit is not particularly limited as long as the light source unit is separately provided from the exposure apparatus main unit. For example, as in the third aspect of the present invention, as the light source unit, An excimer laser device (14) may be used. In this case, since the optical axis can be adjusted without opening the cover of each unit, inconveniences such as leakage of nitrogen gas inside can be prevented.
[0013]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, an embodiment of the present invention will be described with reference to FIGS.
[0014]
FIG. 1 schematically shows a configuration of an exposure apparatus 10 according to an embodiment to which an optical axis adjustment method according to the present invention is applied. FIG. 2 is a schematic plan view of the exposure apparatus 10 shown in FIG. However, in FIG. 2, only the exposure apparatus main body unit portion is shown in a state of being cut along the line AA in FIG. 3 shows a cross-sectional view taken along line BB in FIG. 1, and FIG. 4 shows a cross-sectional view taken along line CC in FIG.
[0015]
As shown in FIG. 1, the exposure apparatus 10 includes an exposure apparatus body unit 12, an excimer laser apparatus 14 as a separate light source unit from the exposure apparatus body unit 12, and a light source (KrF) in the excimer laser apparatus 14. Alternatively, a laser beam from an ArF excimer laser) is guided to the illumination optical system 18 in the exposure apparatus main body unit 12 and a beam matching unit (hereinafter referred to as a relay optical system unit) that connects the excimer laser apparatus 14 and the exposure apparatus main body unit 12. 16) (referred to as “BMU”).
[0016]
The exposure apparatus body unit 12 includes a chamber 12A and an exposure apparatus body housed in the chamber 12A. The main body of the exposure apparatus is a so-called stepper that exposes and transfers a pattern formed on the reticle R onto the wafer W by a step-and-repeat method. The exposure apparatus main body holds the illumination optical system 18, the projection optical system PL, and the wafer W, moves two-dimensionally in a plane orthogonal to the optical axis of the projection optical system PL, and sequentially exposes shot areas on the wafer W. A wafer stage (not shown) for positioning at a position is provided. In the following, for convenience of explanation, the vertical axis, which is the optical axis direction of the projection optical system PL, is defined as the Z axis, and the horizontal direction in FIG. 1 is the X axis and the orthogonal direction in FIG. It shall be defined as an axis.
[0017]
The BMU 16 includes two support columns 16A and 16B. The support column 16A on the exposure apparatus body unit 12 side is a reflection for adjusting the inclination between the optical axis of the exposure apparatus body unit 12 and the optical axis of the BMU 16. A mirror 22 and plane parallel (herving glass) 24 and 26 for adjusting a positional shift (shift) between both optical axes are provided. Further, the column 16B on the excimer laser device 14 side is provided with a reflection mirror 28 for adjusting the inclination between the optical axis of the excimer laser device 14 and the optical axis of the BMU 16, and a positional shift (shift amount) between the optical axes. Plane parallels 30 and 32 for adjustment are provided.
[0018]
The reflection mirror 22 is configured such that the rotation angle around the X axis can be adjusted by a motor 34a, and the rotation angle around the Y axis can be adjusted by a motor 34b (see FIGS. 2 and 3). The inclination of the optical axis of the BMU 16 with respect to the optical axis of the exposure apparatus main unit 12 can be adjusted by adjusting the rotation angles of the reflection mirror 22 about the X axis and the Y axis.
[0019]
Further, the plane parallel 24 is configured to be rotatable around the X axis by the motor 34e, thereby adjusting the shift (shift) of the optical axis in the Y axis direction. Further, the plane parallel 18 is configured to be rotatable around the Y axis by a motor 34f (see FIG. 3), thereby adjusting the shift (shift) of the optical axis in the X axis direction.
[0020]
Similarly to the above, the reflection mirror 28 is configured such that the rotation angle around the X axis can be adjusted by the motor 34c, and the rotation angle around the Y axis can be adjusted by the motor 34d (see FIGS. 2 and 4). The inclination of the optical axis of the BMU 16 with respect to the laser optical axis of the excimer laser device 14 can be adjusted by adjusting the rotation angles of the reflection mirror 28 about the X axis and the Y axis.
[0021]
Further, the plane parallel 30 is configured to be rotatable around the X axis by the motor 34g, thereby adjusting the shift (shift) of the optical axis in the Y axis direction. Further, the plane parallel 32 is configured to be rotatable around the Y axis by a motor 34h (see FIG. 4), thereby adjusting the shift (shift) of the optical axis in the X axis direction.
[0022]
The motors 34a to 34h are controlled by a control signal from a control system (not shown) of the exposure apparatus body unit 12 to adjust the rotation angles of the reflecting mirrors 22 and 28 and the plane parallels 24, 26, 30, and 32 in the above-described directions. As a result, the inclination and shift (positional deviation) of the optical axis of the relay optical system in the BMU 16 with respect to the optical axis of the exposure apparatus main body unit 12 and the excimer laser apparatus 14 can be automatically adjusted regardless of manual operation. It has become.
[0023]
FIG. 5 shows a schematic flowchart of an optical axis adjustment method when the exposure apparatus 10 is installed. 6 to 9 are diagrams for explaining the procedure for adjusting the optical axis along the flowchart of FIG. The procedure for assembling the exposure apparatus and adjusting the optical axis will be described below with reference to FIG. 1 and FIGS.
[0024]
Here, as shown in the plan view of FIG. 2, a plan line 40 is drawn in advance on the floor of the installation floor as a guide for installing the exposure apparatus.
[0025]
(Step 102 in FIG. 5)
First, the heaviest (heavy) exposure apparatus main body unit 12 is installed so as to substantially follow the planned line 40 drawn on the floor surface, and 2 at the entrance 12a (see FIG. 1) of the exposure apparatus main body unit 12. A point reflection reflex sheet holder 38 (see FIG. 6) is attached.
[0026]
(Step 104 in FIG. 5)
Next, the second heaviest excimer laser device 14 is installed so as to substantially follow the planned line 40 on the floor surface, and the two-point reflection reflex sheet holder is also provided at the exit 14a (see FIG. 1) of the excimer laser device 14. 44 is attached.
[0027]
FIG. 6 shows a state in which the processing in step 104 has been completed. As shown in FIG. 6, the reflective reflector sheets 42 a and 42 b serving as two reflectors are attached to the two-point reflective reflector sheet holder 38. These reflection reflex sheets 42a and 42b are collinear with the optical axis of the illumination optical system 18 in the chamber 12A when attached to the exposure apparatus body unit 12 (perpendicular to the opening surface of the entrance 12a shown in FIG. 1). ), And is disposed on the two-point reflective reflex sheet holder 38 so that the distance from the reference point on the optical axis near the entrance 12a is a predetermined known distance. In this case, the reflection point of the reflection mirror 22 in FIG. 1 is determined in design so that it is just an intermediate point (also a machine origin a to be described later) of the reflection reflex sheets 42a and 42b.
[0028]
Similarly, the reflective reflector sheets 42c and 42d as two reflectors are also attached to the two-point reflective reflector sheet holder 44 (see FIG. 6). These reflective reflex sheets 42c and 42d are also on the same straight line as the laser optical axis (perpendicular to the opening surface of the exit port 14a shown in FIG. 1) when attached to the excimer laser device 14, and are emitted. It is arranged on the two-point reflection reflex sheet holder 44 so that the distance from the reference point on the optical axis in the vicinity of the mouth 14a is a predetermined known distance. In this case, the reflection point of the reflection mirror 28 in FIG. 1 is determined by design so that it is just an intermediate point (also a machine point b described later) of the reflection reflex sheets 42c and 42d.
[0029]
(Step 106 in FIG. 5)
Next, the three-dimensional coordinates of the reflective reflex sheets 42a to 42d are measured. Specifically, as shown in FIG. 7, a total station 46, which is a three-dimensional coordinate measuring device, is installed at an appropriate position where the reflective reflex sheets 42a, 42b, 42c, and 42d can be faced. FIG. 7 shows the exposure apparatus body unit 12 and the like viewed from above. Then, the total station 46 is used to reflect the light emitted from the total station 46 with the reflective reflex sheets 42a, 42b, 42c, and 42d as targets, and the reflected light is reflected from the time and direction taken until it returns to the total station 46. The positions (three-dimensional coordinates) of the reflex sheets 42a, 42b, 42c, and 42d are measured. In the total station 46, the three-dimensional coordinates of the positions of the reflective reflex sheets 42a, 42b, 42c, and 42d are calculated with a predetermined reference point inside the total station 46 as the origin. When the measurement of the positions of the reflective reflex sheets 42a, 42b, 42c, and 42d is thus completed, the two-point reflective reflex sheet holders 38 and 44 are removed from the exposure apparatus main unit 12 and the excimer laser apparatus 14, respectively.
[0030]
(Step 108 in FIG. 5)
Next, the BMU 16 is installed so as to be substantially aligned on the planned line 40 between the exposure apparatus main body unit 12 and the excimer laser apparatus 14. This state is shown in FIG. As shown in FIG. 8, reflective left and right reflective sheets 42 e and 42 f as reflective plates are attached to the left and right side surfaces of the BMU 16. These reflection reflex sheets 42e and 42f are designed to be reflection points (designed as mechanical points c and d to be described later) of the above-described reflection mirrors 22 and 28 (see FIG. 1), which are reference points on the optical axis of the optical system inside the BMU 16. Is arranged at a position having a predetermined offset in the Y-axis direction.
[0031]
(Step 110 in FIG. 5)
Next, with the total station 46 being placed at the same point as when the positions of the above-described reflective reflex sheets 42a, 42b, 42c, and 42d are measured, the total reflex sheets 42e and 42f are similarly reflected using the total station 46 as a target. By doing so, the positions of the reflective reflex sheets 42e and 42f are measured, and the three-dimensional coordinates of the reflective reflex sheets 42e and 42f with the reference point in the total station 46 as the origin are measured (see FIG. 9).
[0032]
(Step 112 in FIG. 5)
Next, the total station 46 calculates the inclination and positional deviation of the optical axes of the units 12, 14, and 16. That is, since the total station 46 has a built-in CPU and can measure not only three-dimensional coordinates by distance measurement and angle measurement of the reflective reflex sheet, but also calculation processing of the measurement results. For the three sets of the reflex sheets 42a and 42b, 42c and 42d, and 42e and 42f, the coordinate positions are respectively connected, and the inclination directions of the straight lines connecting the coordinate positions are calculated. In this case, the inclination of the optical axis of the remaining two units with respect to the optical axis of any one of the units 12, 14, and 16 is calculated. The inclination of the optical axis of the BMU 16 with respect to the optical axis of the illumination optical system 18 in the exposure apparatus main body unit 12 from the inclination of the straight line connecting the coordinate positions of the reflective reflex sheets 42a and 42b and the inclination of the straight line connecting the reflective reflex sheets 42e and 42f. Similarly, from the inclination of the straight line connecting the coordinate positions of the reflective reflex sheets 42a and 42b and the inclination of the straight line connecting the coordinate positions of the reflective reflex sheets 42c and 42d, the internal illumination optical system 31b of the exposure apparatus body unit 12 is obtained. The inclination of the optical axis of the excimer laser device 14 with respect to the optical axis is obtained.
[0033]
The shift amount of the optical axis, that is, the positional deviation is obtained as follows. The midpoint of the coordinates of the reflective reflex sheets 42a and 42b (designally coincides with the reflective point of the reflective mirror 22) is determined as the machine origin a. Similarly, the midpoint of the coordinates of the reflective reflex sheets 42c and 42d (designally) , Which coincides with the reflection point of the reflection mirror 28) is defined as the mechanical point b. These points a and b are positioned as shown in FIG. As for the BMU 16, the reflection points of the designed reflection mirrors 22 and 28 are determined as mechanical points c and d as shown in FIG.
[0034]
Then, the coordinate of the machine origin a is obtained from the coordinates of the midpoint of the coordinate positions of the reflection reflex sheets 42a and 42b, and the coordinate of the machine point b is obtained from the coordinates of the midpoint of the coordinate positions of the reflection reflex sheets 42c and 42d. Further, the coordinates of the mechanical points c and d are obtained by subtracting a predetermined offset in the Y-axis direction from the coordinates of the reflective reflex sheets 42e and 42f. Next, the three-dimensional coordinates with the origin at the reference point in the total station 46 for the four machine points a, b, c, d obtained as described above are changed to new three-dimensional coordinates with the machine origin a as the origin. Convert coordinates. The coordinate of the machine point c on the new coordinate system is the position shift (shift amount) of the machine point c on the optical axis of the BMU 16 with respect to the machine origin a on the optical axis of the illumination optical system 18 inside the exposure apparatus main unit 12. Similarly, the difference between the coordinates of the machine point b and the coordinates of the machine point d corresponds to the machine point b on the laser optical axis of the excimer laser device 14 when the optical axis is adjusted with respect to the machine origin a. A positional shift (shift amount) of the mechanical point d on the optical axis of the BMU 16 is given.
[0035]
Then, the measurement data of the optical axis inclination and the shift amount obtained as described above are taken into the data card of the total station 46.
[0036]
(Step 114 in FIG. 5)
Next, the measurement data of the optical axis tilt and the shift amount are input to the exposure apparatus main unit 12, and each mirror and plane parallel of the BMU 16 are controlled to correct the optical axis.
[0037]
Specifically, the data card is set in the exposure apparatus main unit 12, and a measurement command taken in the data card is installed by inputting a command from a keyboard (not shown). In the control system of the exposure apparatus body unit 12, the measurement data is converted into a control signal and sent to the motors 34 a to 34 h equipped in the BMU 16. Thereby, the motors 34a and 34b rotate the reflection mirror 22 around the X and Y axes so that the inclination of the straight line connecting the positions of the reflective reflex sheets 42a and 42b matches the inclination of the straight line connecting the mechanical points c and d. At the same time, the rotation of the plane parallel 24 around the X axis and the rotation of the plane parallel 26 around the Y axis based on the data obtained from the coordinates on the new coordinate system of the machine point c by the motors 34e and 34f. Is adjusted. In this way, the inclination and positional deviation between the optical axis of the exposure apparatus main unit 12 and the optical axis of the BMU 16 are adjusted.
[0038]
Similarly, the motors 34c and 34d rotate the reflection mirror 28 about the X and Y axes so that the inclination of the straight line connecting the positions of the reflective reflex sheets 42c and 42d matches the inclination of the straight line connecting the mechanical points c and d. At the same time, the rotation of the plane parallel 30 around the X axis and the rotation of the plane parallel 32 around the Y axis are adjusted by data obtained from the coordinates of the machine points b and d by the motors 34g and 34h. In this way, the inclination and positional deviation between the optical axis of the excimer laser 23 and the optical axis of the BMU 16 are adjusted.
[0039]
As described above, according to the present embodiment, the reflective reflex sheet is attached as a target to a known point of each unit of the exposure apparatus 10 divided into three units, and the three-dimensional coordinates of the reflective reflex sheet are measured by a total station that is a surveying instrument. The optical axis adjustment mirror and the plane parallel mounted on the BMU 16 are controlled by a motor simply by inputting the tilt angle and shift amount of the optical axis obtained there to the exposure apparatus main unit 12, and the exposure apparatus is installed. The optical axis is adjusted so that the optical axes of the three units are aligned with each other by correcting the inclination and shift amount of the optical axes between the units 12, 14, and 16 generated at the time. Therefore, as in the past, to adjust the tilt error and misalignment of the optical axis between the units, helium neon laser is used to repeatedly adjust the optical components for optical axis adjustment based on the operator's intuition and experience. The troublesome work of doing is unnecessary.
[0040]
Further, according to the present embodiment, since the position is optically measured by the total station, the three-dimensional coordinate value can be obtained very precisely, and accurate optical axis adjustment can be performed. As a result, the operator's skill is not required for optical axis adjustment. In addition, the positioning of each unit can be roughly adjusted accurately, so that the positioning of the units during installation has been difficult due to the heavy weight of each unit. Workability at the time is greatly improved.
[0041]
Furthermore, according to the present embodiment, whether or not it is within the adjustment range of the BMU 16 can be immediately determined from the measurement data obtained by the total station 46. Therefore, when the adjustment is not successful as in the prior art, after the optical axis adjustment is attempted, the BMU 16 Compared with the case where the user finds out that it is not within the adjustment range and performs the adjustment again after re-installation, the work efficiency can be greatly improved.
[0042]
In addition, in an exposure apparatus using an excimer laser as a light source, nitrogen gas is prevented in the illumination optical system 18 and the BMU 16 at the time of shipment from the factory in order to prevent fogging inside the optical system caused by the reaction of the excimer laser with air. However, in the above-described embodiment, it is not necessary to remove the cover at the time of installation at the user's site, so that leakage of this nitrogen gas can also be prevented.
[0043]
Furthermore, in the above-described embodiment, since the optical components for adjusting the optical axis are concentrated on the BMU 16, work such as maintenance can be easily performed.
[0044]
In the above embodiment, the case where the calculation of the tilt angle and the shift amount of the optical axis is performed by the internal processing of the total station has been described, but the present invention is not limited to this. For example, since the exposure apparatus main unit 12 also includes a calculation unit such as a CPU, three-dimensional coordinate data is directly input from the total station to the exposure apparatus main unit 12 to automatically control each optical component of the BMU 16. good.
[0045]
In the above-described embodiment, the case where coordinate calculation is performed using the mechanical origin a set with the exposure apparatus main unit 12 as a reference has been described. However, the present invention is not limited to this, and any unit, for example, the excimer laser device 14 is used. The coordinates of the three units may be calculated using the machine point set with reference to the machine origin.
[0046]
Further, in the above embodiment, the case where the measurement data of the total station is used for optical axis adjustment at the time of installation and assembly of the exposure apparatus 10 has been described. For example, the total station is installed as it is and the position of each unit is continued. Thus, even if the position of each unit changes due to vibration, earthquake, etc., it is possible to correct the positional deviation and inclination with the measurement data of the total station. In this way, even if there is a vibration or an earthquake, no maintenance is required.
[0047]
In the above embodiment, the case where the optical axis adjustment method according to the present invention is applied to a step-and-repeat projection exposure apparatus (stepper) using an excimer laser as a light source has been described. The range is not limited to this, and even a step-and-scan projection exposure apparatus or other exposure apparatus can be suitably applied as long as it uses a light source separately from the exposure apparatus main body. is there.
[0048]
【The invention's effect】
As described above, according to the first to third aspects of the present invention, there is provided an excellent optical axis adjustment method that has not been achieved so far that the optical axis adjustment between units constituting the exposure apparatus can be easily and accurately performed. Can be provided.
[Brief description of the drawings]
FIG. 1 is a drawing schematically showing a configuration of an exposure apparatus according to an embodiment.
FIG. 2 is a schematic plan view of the apparatus of FIG.
FIG. 3 is a cross-sectional view taken along line BB in FIG.
4 is a cross-sectional view taken along the line CC of FIG.
FIG. 5 is a flowchart schematically showing an optical axis adjustment method of the exposure apparatus.
FIG. 6 is a view showing a state in which an exposure apparatus main unit and an excimer laser apparatus are installed.
FIG. 7 is a plan view showing a state in which the three-dimensional coordinates of the reflective reflex sheet attached to the exposure apparatus main unit and the excimer laser apparatus are measured at the total station.
FIG. 8 is a diagram illustrating a state in which a BMU is installed.
FIG. 9 is a plan view showing a state in which the three-dimensional coordinates of the reflective reflex sheet attached to the BMU are measured by the total station.
[Explanation of symbols]
12 Exposure unit
14 Excimer laser device (light source unit)
16 BMU (Relay optical system unit)
18 Illumination optical system
22, 28 Reflection mirror (optical member)
24, 26, 30, 32 Plane parallel (optical member)
42a, 42b, 42c, 42d, 42e, 42f Reflective reflex sheet (reflective plate)
46 Total station (measuring device)

Claims (3)

An exposure apparatus main unit, a light source unit separately from the exposure apparatus main unit, and the light emitted from the light source in the light source unit is guided to the illumination optical system in the exposure apparatus main unit and between the two units. In an optical axis adjustment method of an exposure apparatus provided with a relay optical system unit to be coupled,
The exposure apparatus main unit and the light source unit are respectively installed at predetermined installation positions,
For both units, measure the three-dimensional coordinates of at least two points whose positional relationship with the reference point on the optical axis of each unit is known,
Thereafter, in a state where the exposure apparatus main body unit and the light source unit are connected by the relay optical system unit, at least two-dimensional three-dimensional relations with respect to a reference point on the optical axis of the relay optical system unit are known. Measure the coordinates,
Based on each measurement result, the inclination and shift amount of the optical axis of the remaining two units with respect to the optical axis of any one of the units are calculated,
An optical axis adjustment method for an exposure apparatus, comprising: aligning optical axes of the three units by adjusting an optical member built in at least one of the three units based on the calculation result. 2. The method of adjusting an optical axis of an exposure apparatus according to claim 1, wherein the measurement of the three-dimensional coordinates of at least two points of each unit is performed using an optical measuring device with a reflector as a target. 2. The method of adjusting an optical axis of an exposure apparatus according to claim 1, wherein an excimer laser device is used as the light source unit.

Images